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Oxygen

The Stanford Question Answering Dataset

Oxygen is a chemical element with symbol O and atomic number 8. It is a member of the chalcogen group on the periodic table and is a highly reactive nonmetal and oxidizing agent that readily forms compounds (notably oxides) with most elements. By mass, oxygen is the third-most abundant element in the universe, after hydrogen and helium. At standard temperature and pressure, two atoms of the element bind to form dioxygen, a colorless and odorless diatomic gas with the formula O
2. Diatomic oxygen gas constitutes 20.8% of the Earth's atmosphere. However, monitoring of atmospheric oxygen levels show a global downward trend, because of fossil-fuel burning. Oxygen is the most abundant element by mass in the Earth's crust as part of oxide compounds such as silicon dioxide, making up almost half of the crust's mass.

The atomic number of the periodic table for oxygen?

  • Ground Truth Answers: 88888

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What is the second most abundant element?

  • Ground Truth Answers: heliumheliumheliumheliumhelium

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How many atoms combine to form dioxygen?

  • Ground Truth Answers: two atomstwotwotwotwo

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Roughly, how much oxygen makes up the Earth crust?

  • Ground Truth Answers: almost halfalmost halfhalfalmost halfhalf

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Which gas makes up 20.8% of the Earth's atmosphere?

  • Ground Truth Answers: Diatomic oxygenDiatomic oxygenDiatomic oxygen gasDiatomic oxygenDiatomic oxygen gas

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How much of the earth's atmosphere is diatomic oxygen?

  • Ground Truth Answers: 20.8%20.8%20.8%20.8%20.8%

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What element makes up almost half of the earth's crust by mass?

  • Ground Truth Answers: OxygenOxygenOxygenOxygenOxygen

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What is the atomic number for oxygen?

  • Ground Truth Answers: 88888

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Are atmospheric oxygen levels going up, down, or staying the same?

  • Ground Truth Answers: monitoring of atmospheric oxygen levels show a global downward trenddowndowndowndownward

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What are the three most abundent elements of the universe by mass?

  • Ground Truth Answers: By mass, oxygen is the third-most abundant element in the universe, after hydrogen and heliumoxygen is the third-most abundant element in the universe, after hydrogen and heliumoxygen is the third-most abundant element in the universe, after hydrogen and heliumoxygen is the third-most abundant element in the universe, after hydrogen and heliumBy mass, oxygen is the third-most abundant element in the universe, after hydrogen and helium.

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What is the atomic number of the element oxygen?

  • Ground Truth Answers: 88888

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Of what group in the periodic table is oxygen a member?

  • Ground Truth Answers: chalcogenchalcogenchalcogenchalcogenthe chalcogen group

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What type of compounds does oxygen most commonly form?

  • Ground Truth Answers: oxidesoxidesoxidesoxide compoundsoxide

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Compared to other elements, how abundant does oxygen rank?

  • Ground Truth Answers: thirdthird-mostthirdthird-mostthird

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Under normal conditions, what do two atoms of oxygen form?

  • Ground Truth Answers: dioxygendiatomic gasdioxygendioxygendioxygen

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Many major classes of organic molecules in living organisms, such as proteins, nucleic acids, carbohydrates, and fats, contain oxygen, as do the major inorganic compounds that are constituents of animal shells, teeth, and bone. Most of the mass of living organisms is oxygen as it is a part of water, the major constituent of lifeforms. Oxygen is used in cellular respiration and released by photosynthesis, which uses the energy of sunlight to produce oxygen from water. It is too chemically reactive to remain a free element in air without being continuously replenished by the photosynthetic action of living organisms. Another form (allotrope) of oxygen, ozone (O
3), strongly absorbs UVB radiation and consequently the high-altitude ozone layer helps protect the biosphere from ultraviolet radiation, but is a pollutant near the surface where it is a by-product of smog. At even higher low earth orbit altitudes, sufficient atomic oxygen is present to cause erosion for spacecraft.

Oxygen is released in cellular respiration by?

  • Ground Truth Answers: photosynthesisphotosynthesisphotosynthesisphotosynthesisphotosynthesis

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Photosynthesis uses which energy to for oxygen from water?

  • Ground Truth Answers: sunlightsunlightsunlightthe energy of sunlightsunlight

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_____ Helps the biospher from UV.

  • Ground Truth Answers: high-altitude ozone layerozoneozone layerozone

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What element is found in most organic organisms?

  • Ground Truth Answers: oxygenoxygenoxygenoxygenoxygen

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In what major portion of living things is oxygen found?

  • Ground Truth Answers: waterwaterorganic moleculesinorganic compoundsmass

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What life process produces oxygen in the presence of light?

  • Ground Truth Answers: photosynthesisliving organismsphotosynthesisphotosynthesisphotosynthesis

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From what does photosynthesis get oxygen?

  • Ground Truth Answers: waterwaterwaterwaterwater

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What form of oxygen is composed of three oxygen atoms?

  • Ground Truth Answers: ozoneozoneozoneozone

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In the late 17th century, Robert Boyle proved that air is necessary for combustion. English chemist John Mayow (1641–1679) refined this work by showing that fire requires only a part of air that he called spiritus nitroaereus or just nitroaereus. In one experiment he found that placing either a mouse or a lit candle in a closed container over water caused the water to rise and replace one-fourteenth of the air's volume before extinguishing the subjects. From this he surmised that nitroaereus is consumed in both respiration and combustion.

Who proved that air is necessary for combustion?

  • Ground Truth Answers: Robert BoyleRobert BoyleBoyleRobert Boyle

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What English chemist showed that fire only needed nitoaereus?

  • Ground Truth Answers: John MayowJohn MayowMayowJohn Mayow

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What is consumed in both combustion and respiration?

  • Ground Truth Answers: nitroaereusnitroaereusnitroaereusnitroaereus

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John Mayow died in what year?

  • Ground Truth Answers: 1679167916791679

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What researcher showed that air is a necessity for combustion?

  • Ground Truth Answers: Robert BoyleRobert BoyleBoyleRobert Boyle

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What did John Mayow name the part of air that caused combustion?

  • Ground Truth Answers: nitroaereusspiritus nitroaereusspiritus nitroaereusspiritus nitroaereus or just nitroaereus

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In what century did Mayow and Boyle perform their experiments?

  • Ground Truth Answers: 17th century17th17thlate 17th century

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Besides combustion, for what other action did Mayow show nitroaereus responsible?

  • Ground Truth Answers: respirationrespirationrespirationrespiration

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What chemist showed that fire needed only a part of air?

  • Ground Truth Answers: John MayowJohn MayowMayowJohn Mayow

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In the meantime, on August 1, 1774, an experiment conducted by the British clergyman Joseph Priestley focused sunlight on mercuric oxide (HgO) inside a glass tube, which liberated a gas he named "dephlogisticated air". He noted that candles burned brighter in the gas and that a mouse was more active and lived longer while breathing it. After breathing the gas himself, he wrote: "The feeling of it to my lungs was not sensibly different from that of common air, but I fancied that my breast felt peculiarly light and easy for some time afterwards." Priestley published his findings in 1775 in a paper titled "An Account of Further Discoveries in Air" which was included in the second volume of his book titled Experiments and Observations on Different Kinds of Air. Because he published his findings first, Priestley is usually given priority in the discovery.

"An Account of Further Discoveries in Air" was published by who in 1775?

  • Ground Truth Answers: Joseph PriestleyPriestleyJoseph PriestleyJoseph PriestleyPriestley

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What was the occupation of Joseph Priestley?

  • Ground Truth Answers: clergymanclergymanclergymanclergymanclergyman

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The symbol for mercuric oxide is?

  • Ground Truth Answers: HgOHgOHgOHgOHgO

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By sunlight, what compound did Priestley concentrate on to make the gas he called "dephlogisticated air"?

  • Ground Truth Answers: mercuric oxide (HgO)mercuric oxidemercuric oxidemercuric oxide (HgO)mercuric oxide

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What chemical did Priestley use in his experiments on oxygen?

  • Ground Truth Answers: mercuric oxidemercuric oxidemercuric oxidemercuric oxide (HgO)mercuric oxide

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What did Priestley name the gas his experiment produced?

  • Ground Truth Answers: dephlogisticated airdephlogisticated airdephlogisticated airdephlogisticated air"dephlogisticated air

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In what year did Priestley publish the findings of his experiments?

  • Ground Truth Answers: 17751775177517751775

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Why is Priestley usually given credit for being first to discover oxygen?

  • Ground Truth Answers: published his findings firsthe published his findings firsthe published his findings firsthe published his findings firstBecause he published his findings first

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What effect did breathing Priestley's discovered gas have on the experiment's mouse?

  • Ground Truth Answers: activemore active and lived longerwas more active and lived longermore active and lived longer while breathing itwas more active and lived longer

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One of the first known experiments on the relationship between combustion and air was conducted by the 2nd century BCE Greek writer on mechanics, Philo of Byzantium. In his work Pneumatica, Philo observed that inverting a vessel over a burning candle and surrounding the vessel's neck with water resulted in some water rising into the neck. Philo incorrectly surmised that parts of the air in the vessel were converted into the classical element fire and thus were able to escape through pores in the glass. Many centuries later Leonardo da Vinci built on Philo's work by observing that a portion of air is consumed during combustion and respiration.

What inventor built on to the findings of Philo of Byzantium?

  • Ground Truth Answers: Leonardo da VinciLeonardo da VinciLeonardo da VinciLeonardo da Vincida Vinci

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Pneumatica was written by what Greek writer?

  • Ground Truth Answers: Philo of ByzantiumPhilo of ByzantiumPhiloPhiloPhilo of Byzantium

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In what year was the first known experiments on combustion and air conducted?

  • Ground Truth Answers: 2nd century BCE2nd century BCE2nd century BCE2nd century BCE2nd century BCE

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Philo of Byzantium ____ surmised that air converted to fire

  • Ground Truth Answers: incorrectlyincorrectlyincorrectlyincorrectlyincorrectly

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What early Greek wrote about experiments on air and combustion?

  • Ground Truth Answers: Philo of ByzantiumPhilo of ByzantiumPhiloPhiloPhilo of Byzantium

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What did Philo incorrectly assume that the air became?

  • Ground Truth Answers: firethe classical element firefirethe classical element firefire

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What was the title of Philo's work?

  • Ground Truth Answers: PneumaticaPneumaticaPneumaticaPneumaticaPneumatica

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What famous artist later further investigated Philo's experiments?

  • Ground Truth Answers: Leonardo da VinciLeonardo da VinciLeonardo da VinciLeonardo da Vincida Vinci

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Of what did da Vinci think a part was consumed during combustion?

  • Ground Truth Answers: airairairair

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Highly concentrated sources of oxygen promote rapid combustion. Fire and explosion hazards exist when concentrated oxidants and fuels are brought into close proximity; an ignition event, such as heat or a spark, is needed to trigger combustion. Oxygen is the oxidant, not the fuel, but nevertheless the source of most of the chemical energy released in combustion. Combustion hazards also apply to compounds of oxygen with a high oxidative potential, such as peroxides, chlorates, nitrates, perchlorates, and dichromates because they can donate oxygen to a fire.

What is needed to make combustion happen?

  • Ground Truth Answers: heat or a sparkoxygenan ignition eventan ignition event, such as heat or a sparkan ignition event

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Combustion is caused by an oxidant and a fuel. What role does oxygen play in combustion?

  • Ground Truth Answers: Oxygen is the oxidantthe oxidantoxidantoxidantoxidant

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Peroxides, nitrates and dichromates are examples of what type of compounds?

  • Ground Truth Answers: compounds of oxygen with a high oxidativecompounds of oxygen with a high oxidative potentialcompounds of oxygen with a high oxidative potentialcompounds of oxygen with a high oxidative potentialcompounds of oxygen with a high oxidative potential

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Although not a fuel ___ is the chemical compound the generates the most occurrence of explosions.

  • Ground Truth Answers: OxygenOxygenOxygenOxygenOxygen

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What is a spark or heat to the progress of a fire?

  • Ground Truth Answers: ignition eventignition eventan ignition eventignition eventan ignition event

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Rather than the fuel, what is oxygen to a fire?

  • Ground Truth Answers: oxidantthe oxidantoxidantthe oxidantoxidant

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What can concentrated oxygen produce?

  • Ground Truth Answers: rapid combustionrapid combustionrapid combustionrapid combustionrapid combustion

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What does oxygen the basis for in combustion?

  • Ground Truth Answers: chemical energychemical energychemical energymost of the chemical energy

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What other sources of high oxidative potential can add to a fire?

  • Ground Truth Answers: compounds of oxygenperoxides, chlorates, nitrates, perchlorates, and dichromatesperoxides, chlorates, nitrates, perchlorates, and dichromatesperoxides, chlorates, nitrates, perchlorates, and dichromatesperoxides, chlorates, nitrates, perchlorates, and dichromates

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Concentrated O
2 will allow combustion to proceed rapidly and energetically. Steel pipes and storage vessels used to store and transmit both gaseous and liquid oxygen will act as a fuel; and therefore the design and manufacture of O
2 systems requires special training to ensure that ignition sources are minimized. The fire that killed the Apollo 1 crew in a launch pad test spread so rapidly because the capsule was pressurized with pure O
2 but at slightly more than atmospheric pressure, instead of the 1⁄3 normal pressure that would be used in a mission.[k]

What chemical element was the cause of the Apollo 1 disastrous outcome?

  • Ground Truth Answers: pure O

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______ In both liquid and gas form can fastly result in an exlposion.

  • Ground Truth Answers: oxygenoxygenoxygen

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To ensure safety of future space missions Oxygen was used at _____ of the normal pressure.

  • Ground Truth Answers: 1⁄31⁄31⁄31⁄31⁄3 normal pressure

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To reduce the chances of combustion ___ is required for safely handeling pure O.

  • Ground Truth Answers: special trainingspecial trainingspecial training to ensure that ignition sources are minimizedspecial trainingspecial training

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What will concentrated oxygen greatly speed up?

  • Ground Truth Answers: combustioncombustioncombustioncombustioncombustion

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Because of the danger inherent in concentrated oxygen, what is a concern about keeping it?

  • Ground Truth Answers: storage vesselsfireensure that ignition sources are minimizedspecial training to ensure that ignition sources are minimized

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What does the transport and storage demand for safety in dealing with oxygen?

  • Ground Truth Answers: special trainingspecial trainingspecial training to ensure that ignition sources are minimizedspecial trainingspecial training

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Who did a pressurized oxygen cabin fire kill?

  • Ground Truth Answers: Apollo 1 crewthe Apollo 1 crewthe Apollo 1 crewApollo 1 crewthe Apollo 1 crew

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Oxygen is present in the atmosphere in trace quantities in the form of carbon dioxide (CO
2). The Earth's crustal rock is composed in large part of oxides of silicon (silica SiO
2, as found in granite and quartz), aluminium (aluminium oxide Al
2O
3, in bauxite and corundum), iron (iron(III) oxide Fe
2O
3, in hematite and rust), and calcium carbonate (in limestone). The rest of the Earth's crust is also made of oxygen compounds, in particular various complex silicates (in silicate minerals). The Earth's mantle, of much larger mass than the crust, is largely composed of silicates of magnesium and iron.

Granite is made up largely of what chemical compound?

  • Ground Truth Answers: oxides of siliconsiliconsilicon

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Oxygen exists in the atmosphere by way of what?

  • Ground Truth Answers: carbon dioxidecarbon dioxidecarbon dioxidecarbon dioxide

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Silicates of magnesium and iron make up of the Earth's ___

  • Ground Truth Answers: mantlemantlemantleThe Earth's mantlemantle

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In what compound is oxygen found in small amounts in the atmosphere?

  • Ground Truth Answers: carbon dioxidecarbon dioxide

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What geologic feature is composed of oxygen oxides?

  • Ground Truth Answers: Earth's crustal rockcrustal rockEarth's crustThe Earth's crustcrustal rock

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What part of the Earth is composed of mostly of silicates of iron and magnesium?

  • Ground Truth Answers: Earth's mantleThe Earth's mantlemantleThe Earth's mantlemantle

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What part of the Earth's geological structure is larger than the crust?

  • Ground Truth Answers: mantleThe Earth's mantlemantleThe Earth's mantlemantle

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Aside from oxides, what other compounds comprise a large portion of the Earth's crust?

  • Ground Truth Answers: complex silicatescomplex silicatessilicatessilicatessilicates (in silicate minerals)

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John Dalton's original atomic hypothesis assumed that all elements were monatomic and that the atoms in compounds would normally have the simplest atomic ratios with respect to one another. For example, Dalton assumed that water's formula was HO, giving the atomic mass of oxygen as 8 times that of hydrogen, instead of the modern value of about 16. In 1805, Joseph Louis Gay-Lussac and Alexander von Humboldt showed that water is formed of two volumes of hydrogen and one volume of oxygen; and by 1811 Amedeo Avogadro had arrived at the correct interpretation of water's composition, based on what is now called Avogadro's law and the assumption of diatomic elemental molecules.[a]

What did John Dalton think that all elements were in number present in compounds?

  • Ground Truth Answers: monatomicmonatomicmonatomicmonatomicmonatomic

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What did Dalton think the atomic ratios were between atoms in compounds?

  • Ground Truth Answers: simplestsimplestsimplestsimplestthe simplest

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What was Dalton's erroneous formula for water?

  • Ground Truth Answers: HOHOHOHOHO

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What element did Gay-Lussac and von Humboldt discover was present in twice the amount of oxygen in water?

  • Ground Truth Answers: hydrogenhydrogenhydrogenhydrogenhydrogen

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What theory was arrived at in 1811 that presented the assumption of diatomic molecules?

  • Ground Truth Answers: Avogadro's lawAvogadro's lawAvogadro's lawthe correct interpretation of water's compositionAvogadro's law

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Highly combustible materials that leave little residue, such as wood or coal, were thought to be made mostly of phlogiston; whereas non-combustible substances that corrode, such as iron, contained very little. Air did not play a role in phlogiston theory, nor were any initial quantitative experiments conducted to test the idea; instead, it was based on observations of what happens when something burns, that most common objects appear to become lighter and seem to lose something in the process. The fact that a substance like wood gains overall weight in burning was hidden by the buoyancy of the gaseous combustion products. Indeed, one of the first clues that the phlogiston theory was incorrect was that metals, too, gain weight in rusting (when they were supposedly losing phlogiston).

Of what were materials that left little residue thought to contain?

  • Ground Truth Answers: phlogistonphlogistonphlogistonphlogistonphlogiston

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What type of combustible materials were considered to have little philogiston?

  • Ground Truth Answers: non-combustiblenon-combustible substances that corrodewoodwood

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What distinct quality of combustion was absent from philogiston theory?

  • Ground Truth Answers: AirAirAirAira substance like wood gains overall weight in burning

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What material's weight gain during rusting was an early clue that philogiston theory was wrong?

  • Ground Truth Answers: metalsmetalsmetalsmetalsmetals

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What characteristic due most items display after burning?

  • Ground Truth Answers: become lighterappear to become lighterappear to become lighterappear to become lighter and seem to lose something in the processlighter

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In this dioxygen, the two oxygen atoms are chemically bonded to each other. The bond can be variously described based on level of theory, but is reasonably and simply described as a covalent double bond that results from the filling of molecular orbitals formed from the atomic orbitals of the individual oxygen atoms, the filling of which results in a bond order of two. More specifically, the double bond is the result of sequential, low-to-high energy, or Aufbau, filling of orbitals, and the resulting cancellation of contributions from the 2s electrons, after sequential filling of the low σ and σ* orbitals; σ overlap of the two atomic 2p orbitals that lie along the O-O molecular axis and π overlap of two pairs of atomic 2p orbitals perpendicular to the O-O molecular axis, and then cancellation of contributions from the remaining two of the six 2p electrons after their partial filling of the lowest π and π* orbitals.

How is dioxygen most simply described?

  • Ground Truth Answers: covalent double bonda covalent double bonda covalent double bond that results from the filling of molecular orbitals formed from the atomic orbitals of the individual oxygen atomsa covalent double bonda covalent double bond that results from the filling of molecular orbitals formed from the atomic orbitals of the individual oxygen atoms

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What is the bond order of dioxygen molecules?

  • Ground Truth Answers: twotwotwotwotwo

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What is a descriptive term for a low-to-high energy bond?

  • Ground Truth Answers: AufbauAufbauAufbauAufbauAufbau

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In dioxygen how are the two oxygen atoms bonded together?

  • Ground Truth Answers: chemicallychemicallya covalent double bonda covalent double bonda covalent double bond

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Of what does the covalent double bond result from ?

  • Ground Truth Answers: molecular orbitalsfilling of molecular orbitalsthe filling of molecular orbitals formed from the atomic orbitals of the individual oxygen atomsthe filling of molecular orbitals formed from the atomic orbitals of the individual oxygen atomsthe filling of molecular orbitals formed from the atomic orbitals of the individual oxygen atoms

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Oxygen was discovered independently by Carl Wilhelm Scheele, in Uppsala, in 1773 or earlier, and Joseph Priestley in Wiltshire, in 1774, but Priestley is often given priority because his work was published first. The name oxygen was coined in 1777 by Antoine Lavoisier, whose experiments with oxygen helped to discredit the then-popular phlogiston theory of combustion and corrosion. Its name derives from the Greek roots ὀξύς oxys, "acid", literally "sharp", referring to the sour taste of acids and -γενής -genes, "producer", literally "begetter", because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition. Common uses of oxygen includes the production cycle of steel, plastics and textiles, brazing, welding and cutting of steels and other metals, rocket propellant, in oxygen therapy and life support systems in aircraft, submarines, spaceflight and diving.

When did Carl Wilhelm Scheele discover oxygen?

  • Ground Truth Answers: 17731773177317731773 or earlier

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In what year did Joseph Priestley recognize oxygen?

  • Ground Truth Answers: 17741774177417741774

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What gave Priestley the claim to being the first discovered of oxygen?

  • Ground Truth Answers: work was published firsthis work was published firsthis work was published firsthis work was published firstpublished first

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What researcher first used the word oxygen ?

  • Ground Truth Answers: Antoine LavoisierAntoine LavoisierAntoine LavoisierAntoine LavoisierLavoisier

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What previous work did Lavoisier experiments discredit?

  • Ground Truth Answers: phlogiston theoryphlogiston theory of combustion and corrosionphlogiston theory of combustion and corrosionphlogiston theory of combustion and corrosionphlogiston theory

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This combination of cancellations and σ and π overlaps results in dioxygen's double bond character and reactivity, and a triplet electronic ground state. An electron configuration with two unpaired electrons as found in dioxygen (see the filled π* orbitals in the diagram), orbitals that are of equal energy—i.e., degenerate—is a configuration termed a spin triplet state. Hence, the ground state of the O
2 molecule is referred to as triplet oxygen.[b] The highest energy, partially filled orbitals are antibonding, and so their filling weakens the bond order from three to two. Because of its unpaired electrons, triplet oxygen reacts only slowly with most organic molecules, which have paired electron spins; this prevents spontaneous combustion.

What is the term for the arrangement of two unpaired electrons in dioxygen?

  • Ground Truth Answers: spin triplet statespin triplet statespin triplet statespin triplet statea spin triplet state

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How is the O2 molecule referred to in its ground state?

  • Ground Truth Answers: triplet oxygenOtriplet oxygentriplet oxygentriplet oxygen

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What causes triplet oxygen to react slowly?

  • Ground Truth Answers: unpaired electronsits unpaired electronsits unpaired electronsBecause of its unpaired electronsunpaired electrons

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What type of combustion does the slow reaction of triplet oxygen prevent?

  • Ground Truth Answers: spontaneousspontaneous combustionspontaneousspontaneousspontaneous combustion

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What are the weakly filled higher orbitals of oxygen?

  • Ground Truth Answers: antibondingantibondingantibondingantibondingantibonding

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In one experiment, Lavoisier observed that there was no overall increase in weight when tin and air were heated in a closed container. He noted that air rushed in when he opened the container, which indicated that part of the trapped air had been consumed. He also noted that the tin had increased in weight and that increase was the same as the weight of the air that rushed back in. This and other experiments on combustion were documented in his book Sur la combustion en général, which was published in 1777. In that work, he proved that air is a mixture of two gases; 'vital air', which is essential to combustion and respiration, and azote (Gk. ἄζωτον "lifeless"), which did not support either. Azote later became nitrogen in English, although it has kept the name in French and several other European languages.

What did Lavoisier conclude was consumed by combustion in his experiments?

  • Ground Truth Answers: airairairpart of the trapped airair

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In what way did Lavoisier see that the tin he used in his experiment had increased?

  • Ground Truth Answers: weightweightweightthat increase was the same as the weight of the air that rushed back inthe tin had increased in weight and that increase was the same as the weight of the air that rushed back in

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What did Lavoisier perceive the air had lost as much as the tin had gained

  • Ground Truth Answers: weightweightweightweightweight

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In what year did Lavoisier publish his work on combustion?

  • Ground Truth Answers: 17771777177717771777

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What second part of air was deemed lifeless by Lavoisier?

  • Ground Truth Answers: azoteazoteazoteazoteazote

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Trioxygen (O
3) is usually known as ozone and is a very reactive allotrope of oxygen that is damaging to lung tissue. Ozone is produced in the upper atmosphere when O
2 combines with atomic oxygen made by the splitting of O
2 by ultraviolet (UV) radiation. Since ozone absorbs strongly in the UV region of the spectrum, the ozone layer of the upper atmosphere functions as a protective radiation shield for the planet. Near the Earth's surface, it is a pollutant formed as a by-product of automobile exhaust. The metastable molecule tetraoxygen (O
4) was discovered in 2001, and was assumed to exist in one of the six phases of solid oxygen. It was proven in 2006 that this phase, created by pressurizing O
2 to 20 GPa, is in fact a rhombohedral O
8 cluster. This cluster has the potential to be a much more powerful oxidizer than either O
2 or O
3 and may therefore be used in rocket fuel. A metallic phase was discovered in 1990 when solid oxygen is subjected to a pressure of above 96 GPa and it was shown in 1998 that at very low temperatures, this phase becomes superconducting.

What is the name for O3 most often used?

  • Ground Truth Answers: ozoneozoneozoneTrioxygenOzone

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Of what is ozone a reactive part of oxygen?

  • Ground Truth Answers: allotropeallotropeallotropeallotropeallotrope

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What does ozone's characteristic to cause damage effect?

  • Ground Truth Answers: lung tissuelung tissuelung tissuelunglung tissue

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What function does ozone perform for the planet?

  • Ground Truth Answers: protective radiation shieldprotective radiation shieldprotective radiation shieldradiation shielda protective radiation shield

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What light radiation does ozone absorb?

  • Ground Truth Answers: UVultravioletUVultraviolet (UV)ultraviolet

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The common allotrope of elemental oxygen on Earth is called dioxygen, O
2. It is the form that is a major part of the Earth's atmosphere (see Occurrence). O2 has a bond length of 121 pm and a bond energy of 498 kJ·mol−1, which is smaller than the energy of other double bonds or pairs of single bonds in the biosphere and responsible for the exothermic reaction of O2 with any organic molecule. Due to its energy content, O2 is used by complex forms of life, such as animals, in cellular respiration (see Biological role). Other aspects of O
2 are covered in the remainder of this article.

What is the most common form of oxygen on the planet?

  • Ground Truth Answers: dioxygendioxygendioxygendioxygen

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What is the scientific designation of oxygen?

  • Ground Truth Answers: O2

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What part the composition of the Earth's atmosphere is comprised of oxygen?

  • Ground Truth Answers: majormajormajora major partmajor

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What characteristic of oxygen makes it necessary to life?

  • Ground Truth Answers: energy contentits energy contentenergy contentenergy contentits energy content

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For what purpose is oxygen used by animal life?

  • Ground Truth Answers: cellular respirationcellular respirationcellular respirationin cellular respirationcellular respiration

  • Prediction:

In 1891 Scottish chemist James Dewar was able to produce enough liquid oxygen to study. The first commercially viable process for producing liquid oxygen was independently developed in 1895 by German engineer Carl von Linde and British engineer William Hampson. Both men lowered the temperature of air until it liquefied and then distilled the component gases by boiling them off one at a time and capturing them. Later, in 1901, oxyacetylene welding was demonstrated for the first time by burning a mixture of acetylene and compressed O
2. This method of welding and cutting metal later became common.

What chemist managed to make enough liquid oxygen to use for study?

  • Ground Truth Answers: James DewarJames DewarJames DewarDewarJames Dewar

  • Prediction:

In what year did Dewar experiment on liquid oxygen?

  • Ground Truth Answers: 18911891189118911891

  • Prediction:

When was liquid oxygen developed for commercial use?

  • Ground Truth Answers: 18951895189518951895

  • Prediction:

What welding process was demonstrated in 1901?

  • Ground Truth Answers: oxyacetyleneoxyacetylene weldingoxyacetylene weldingoxyacetylene weldingoxyacetylene

  • Prediction:

Oxygen is more soluble in water than nitrogen is. Water in equilibrium with air contains approximately 1 molecule of dissolved O
2 for every 2 molecules of N
2, compared to an atmospheric ratio of approximately 1:4. The solubility of oxygen in water is temperature-dependent, and about twice as much (14.6 mg·L−1) dissolves at 0 °C than at 20 °C (7.6 mg·L−1). At 25 °C and 1 standard atmosphere (101.3 kPa) of air, freshwater contains about 6.04 milliliters (mL) of oxygen per liter, whereas seawater contains about 4.95 mL per liter. At 5 °C the solubility increases to 9.0 mL (50% more than at 25 °C) per liter for water and 7.2 mL (45% more) per liter for sea water.

What component of water is more soluble than nitrogen?

  • Ground Truth Answers: OxygenOxygenOxygenOxygenOxygen

  • Prediction:

Upon what chemical characteristic is oxygen's solubility dependent?

  • Ground Truth Answers: temperaturetemperaturetemperaturetemperaturetemperature

  • Prediction:

How much oxygen is found is a liter of fresh water under normal conditions?

  • Ground Truth Answers: 6.04 milliliters6.04 milliliters6.04 milliliters6.04 milliliters6.04 milliliters

  • Prediction:

In what type of water does oxygen dissolve more slowly?

  • Ground Truth Answers: seawaterseawaterseawaterseawatersea water

  • Prediction:

How much more oxygen dissolves at 0 degrees C than at 20 degrees C?

  • Ground Truth Answers: twice50% moreabout twice as muchtwice as muchtwice

  • Prediction:

Oxygen is the most abundant chemical element by mass in the Earth's biosphere, air, sea and land. Oxygen is the third most abundant chemical element in the universe, after hydrogen and helium. About 0.9% of the Sun's mass is oxygen. Oxygen constitutes 49.2% of the Earth's crust by mass and is the major component of the world's oceans (88.8% by mass). Oxygen gas is the second most common component of the Earth's atmosphere, taking up 20.8% of its volume and 23.1% of its mass (some 1015 tonnes).[d] Earth is unusual among the planets of the Solar System in having such a high concentration of oxygen gas in its atmosphere: Mars (with 0.1% O
2 by volume) and Venus have far lower concentrations. The O
2 surrounding these other planets is produced solely by ultraviolet radiation impacting oxygen-containing molecules such as carbon dioxide.

Where does oxygen rank by mass in the planet's biosphere?

  • Ground Truth Answers: most abundantmostmost abundantmost abundantmost abundant

  • Prediction:

How is oxygen ranked as abundant in the universe?

  • Ground Truth Answers: thirdthirdthirdthird most abundantthird

  • Prediction:

How much of the sun is made up of oxygen?

  • Ground Truth Answers: 0.9%0.9%About 0.9%0.9%0.9%

  • Prediction:

Where by mass is oxygen a major part?

  • Ground Truth Answers: world's oceansthe world's oceansin the Earth's biosphere, air, sea and landoceansthe world's oceans

  • Prediction:

How is oxygen produced from carbon dioxide on the other planets of the solar system?

  • Ground Truth Answers: ultraviolet radiationultraviolet radiationultraviolet radiation impacting oxygen-containing moleculesultraviolet radiation impacting oxygen-containing moleculesultraviolet radiation impacting oxygen-containing molecules such as carbon dioxide

  • Prediction:

By the late 19th century scientists realized that air could be liquefied, and its components isolated, by compressing and cooling it. Using a cascade method, Swiss chemist and physicist Raoul Pierre Pictet evaporated liquid sulfur dioxide in order to liquefy carbon dioxide, which in turn was evaporated to cool oxygen gas enough to liquefy it. He sent a telegram on December 22, 1877 to the French Academy of Sciences in Paris announcing his discovery of liquid oxygen. Just two days later, French physicist Louis Paul Cailletet announced his own method of liquefying molecular oxygen. Only a few drops of the liquid were produced in either case so no meaningful analysis could be conducted. Oxygen was liquified in stable state for the first time on March 29, 1883 by Polish scientists from Jagiellonian University, Zygmunt Wróblewski and Karol Olszewski.

By what century did researchers see that they could liquefy air?

  • Ground Truth Answers: late 19th19th19thlate 19th century19th

  • Prediction:

By what means were scientists able to liquefy air?

  • Ground Truth Answers: compressing and coolingcompressing and coolingcascade methodcompressing and cooling itcompressing and cooling

  • Prediction:

What scientist told the French Academy of Sciences that he had found how to liquefy oxygen?

  • Ground Truth Answers: Raoul Pierre PictetRaoul Pierre PictetPierre PictetPictetRaoul Pierre Pictet

  • Prediction:

What minor amount of liquid oxygen was produced by early French experimenters?

  • Ground Truth Answers: few dropsa few dropsa few dropsa few dropsOnly a few drops

  • Prediction:

On what date was oxygen liquefied in a stable form?

  • Ground Truth Answers: March 29, 1883March 29, 1883March 29, 1883March 29, 1883March 29, 1883

  • Prediction:

Planetary geologists have measured different abundances of oxygen isotopes in samples from the Earth, the Moon, Mars, and meteorites, but were long unable to obtain reference values for the isotope ratios in the Sun, believed to be the same as those of the primordial solar nebula. Analysis of a silicon wafer exposed to the solar wind in space and returned by the crashed Genesis spacecraft has shown that the Sun has a higher proportion of oxygen-16 than does the Earth. The measurement implies that an unknown process depleted oxygen-16 from the Sun's disk of protoplanetary material prior to the coalescence of dust grains that formed the Earth.

What celestial object eluded efforts to measure oxygen?

  • Ground Truth Answers: Sunthe Sunthe SunSunthe Sun

  • Prediction:

What molecule does the Sun have in higher proportion than Earth?

  • Ground Truth Answers: oxygen-16oxygen-16oxygen-16oxygen-16oxygen-16

  • Prediction:

What spacecraft contained data to determine the oxygen content of the Sun?

  • Ground Truth Answers: Genesis spacecraftGenesisGenesisGenesisGenesis

  • Prediction:

What type of process was involved the the depletion of the Sun's oxygen 16?

  • Ground Truth Answers: unknownan unknown processunknownunknownan unknown process

  • Prediction:

Before the formation of which planet, did Sol lose oxygen 16?

  • Ground Truth Answers: EarthEarthEarththe EarthEarth

  • Prediction:

Singlet oxygen is a name given to several higher-energy species of molecular O
2 in which all the electron spins are paired. It is much more reactive towards common organic molecules than is molecular oxygen per se. In nature, singlet oxygen is commonly formed from water during photosynthesis, using the energy of sunlight. It is also produced in the troposphere by the photolysis of ozone by light of short wavelength, and by the immune system as a source of active oxygen. Carotenoids in photosynthetic organisms (and possibly also in animals) play a major role in absorbing energy from singlet oxygen and converting it to the unexcited ground state before it can cause harm to tissues.

What is the name for a form of oxygen in which electrons are paired?

  • Ground Truth Answers: SingletSinglet oxygenSinglet oxygenSingletSinglet oxygen

  • Prediction:

To what is singlet oxygen more reactive?

  • Ground Truth Answers: organic moleculescommon organic moleculescommon organic moleculescommon organic moleculescommon organic molecules

  • Prediction:

In what process is singlet oxygen usually formed?

  • Ground Truth Answers: photosynthesisphotosynthesisphotosynthesisphotosynthesisphotosynthesis

  • Prediction:

By what process is singlet oxygen made in the tropophere?

  • Ground Truth Answers: photolysis of ozonephotolysis of ozonephotolysis of ozone by light of short wavelengthphotolysis of ozone by light of short wavelengthphotolysis

  • Prediction:

What objects in organisms absorb singlet oxygen to prevent harm?

  • Ground Truth Answers: CarotenoidsCarotenoidsCarotenoidsCarotenoidsCarotenoids

  • Prediction:

Paleoclimatologists measure the ratio of oxygen-18 and oxygen-16 in the shells and skeletons of marine organisms to determine what the climate was like millions of years ago (see oxygen isotope ratio cycle). Seawater molecules that contain the lighter isotope, oxygen-16, evaporate at a slightly faster rate than water molecules containing the 12% heavier oxygen-18; this disparity increases at lower temperatures. During periods of lower global temperatures, snow and rain from that evaporated water tends to be higher in oxygen-16, and the seawater left behind tends to be higher in oxygen-18. Marine organisms then incorporate more oxygen-18 into their skeletons and shells than they would in a warmer climate. Paleoclimatologists also directly measure this ratio in the water molecules of ice core samples that are up to several hundreds of thousands of years old.

What group of scientists seek to measure the amounts of oxygen in marine animals?

  • Ground Truth Answers: PaleoclimatologistsPaleoclimatologistsPaleoclimatologistsPaleoclimatologistsPaleoclimatologists

  • Prediction:

About what weather feature do paleoclimatologists want information ?

  • Ground Truth Answers: climateclimatetemperaturesclimatewhat the climate was like millions of years ago

  • Prediction:

How much heavier is oxygen 18 than oxygen 16?

  • Ground Truth Answers: 12%12%12%12%12%

  • Prediction:

What form of oxygen do marine animals acquire in greater amounts during cooler climatic conditions?

  • Ground Truth Answers: oxygen-18oxygen-18oxygen-16oxygen-18oxygen-18

  • Prediction:

During what type of climate is oxygen 18 in seawater at higher levels?

  • Ground Truth Answers: lower global temperaturesperiods of lower global temperatureslower temperaturesperiods of lower global temperatureslower global temperatures

  • Prediction:

Oxygen presents two spectrophotometric absorption bands peaking at the wavelengths 687 and 760 nm. Some remote sensing scientists have proposed using the measurement of the radiance coming from vegetation canopies in those bands to characterize plant health status from a satellite platform. This approach exploits the fact that in those bands it is possible to discriminate the vegetation's reflectance from its fluorescence, which is much weaker. The measurement is technically difficult owing to the low signal-to-noise ratio and the physical structure of vegetation; but it has been proposed as a possible method of monitoring the carbon cycle from satellites on a global scale.

At what wavelength do the spectrophotometric bands peak?

  • Ground Truth Answers: 687 and 760 nm687 and 760 nm687 and 760 nm687 and 760 nm687 and 760 nm

  • Prediction:

To monitor what event would measuring radiance from vegetation provide information?

  • Ground Truth Answers: carbon cycleplant health statusthe carbon cycleplant health statuscarbon cycle

  • Prediction:

From where would scientists like measure vegetation radiance?

  • Ground Truth Answers: satellite platforma satellite platformsatellitesa satellite platformsatellite

  • Prediction:

On what scale would scientists show measurements of vegetation?

  • Ground Truth Answers: globala global scaleglobalglobala global scale

  • Prediction:

What style of sensing do scientist like to use to measure global radiance?

  • Ground Truth Answers: remote sensingremoteremoteremote sensingremote

  • Prediction:

In the triplet form, O
2 molecules are paramagnetic. That is, they impart magnetic character to oxygen when it is in the presence of a magnetic field, because of the spin magnetic moments of the unpaired electrons in the molecule, and the negative exchange energy between neighboring O
2 molecules. Liquid oxygen is attracted to a magnet to a sufficient extent that, in laboratory demonstrations, a bridge of liquid oxygen may be supported against its own weight between the poles of a powerful magnet.[c]

What magnetic character do triplet O2 have?

  • Ground Truth Answers: paramagneticparamagneticparamagneticparamagneticparamagnetic

  • Prediction:

In experiments, a bridge of what element can be built between poles of a magnet?

  • Ground Truth Answers: Liquid oxygenliquid oxygenliquid oxygenoxygenliquid oxygen

  • Prediction:

The spin of what can produce a magnetic effect to oxygen molecules?

  • Ground Truth Answers: unpaired electronsunpaired electronsunpaired electronsunpaired electrons in the moleculeunpaired electrons

  • Prediction:

What kind of field is necessary to produce a magnet effect in oxygen molecules?

  • Ground Truth Answers: magnetic fieldmagneticmagneticmagnetic fieldmagnetic

  • Prediction:

What device is used to test the magnetic attractions involved in liquid oxygen?

  • Ground Truth Answers: powerful magneta powerful magneta powerful magneta powerful magnetmagnet

  • Prediction:

Reactive oxygen species, such as superoxide ion (O−
2) and hydrogen peroxide (H
2O
2), are dangerous by-products of oxygen use in organisms. Parts of the immune system of higher organisms create peroxide, superoxide, and singlet oxygen to destroy invading microbes. Reactive oxygen species also play an important role in the hypersensitive response of plants against pathogen attack. Oxygen is toxic to obligately anaerobic organisms, which were the dominant form of early life on Earth until O
2 began to accumulate in the atmosphere about 2.5 billion years ago during the Great Oxygenation Event, about a billion years after the first appearance of these organisms.

What do the reactive forms of oxygen produce in organisms?

  • Ground Truth Answers: dangerous by-productsthe immune systemhypersensitive response of plants against pathogen attackdangerous by-products of oxygen use in organisms

  • Prediction:

For what purpose do organisms make peroxide and superoxide?

  • Ground Truth Answers: destroy invading microbesto destroy invading microbesdestroy invading microbesto destroy invading microbesdestroy invading microbes

  • Prediction:

Against what does reactive oxygen play in plant defense?

  • Ground Truth Answers: pathogen attackpathogen attackpathogen attackpathogen attackpathogen

  • Prediction:

To what type of organisms is oxygen toxic?

  • Ground Truth Answers: anaerobicobligately anaerobic organismsobligately anaerobicobligately anaerobicobligately anaerobic organisms

  • Prediction:

When did O2 begin to acculturate in the atmosphere?

  • Ground Truth Answers: 2.5 billion years ago2.5 billion years agoabout 2.5 billion years agoabout 2.5 billion years ago2.5 billion years ago during the Great Oxygenation Event

  • Prediction:

Oxygen condenses at 90.20 K (−182.95 °C, −297.31 °F), and freezes at 54.36 K (−218.79 °C, −361.82 °F). Both liquid and solid O
2 are clear substances with a light sky-blue color caused by absorption in the red (in contrast with the blue color of the sky, which is due to Rayleigh scattering of blue light). High-purity liquid O
2 is usually obtained by the fractional distillation of liquefied air. Liquid oxygen may also be produced by condensation out of air, using liquid nitrogen as a coolant. It is a highly reactive substance and must be segregated from combustible materials.

At what temperature will oxygen condense?

  • Ground Truth Answers: 90.20 K90.20 K90.20 K (−182.95 °C, −297.31 °F)90.20 K90.20 K (−182.95 °C, −297.31 °F)

  • Prediction:

What is the clarity of liquid oxygen?

  • Ground Truth Answers: clearclear substances with a light sky-blue colorclearclearclear

  • Prediction:

What substance is used to make high quality liquid O2?

  • Ground Truth Answers: liquefied airliquefied airliquefied airairliquefied air

  • Prediction:

What element is used as a coolant in the process of making liquid oxygen?

  • Ground Truth Answers: liquid nitrogenliquid nitrogenliquid nitrogenliquid nitrogennitrogen

  • Prediction:

From what type of materials must liquid oxygen be separated?

  • Ground Truth Answers: combustible materialscombustible materialscombustiblecombustiblecombustible materials

  • Prediction:

Free oxygen also occurs in solution in the world's water bodies. The increased solubility of O
2 at lower temperatures (see Physical properties) has important implications for ocean life, as polar oceans support a much higher density of life due to their higher oxygen content. Water polluted with plant nutrients such as nitrates or phosphates may stimulate growth of algae by a process called eutrophication and the decay of these organisms and other biomaterials may reduce amounts of O
2 in eutrophic water bodies. Scientists assess this aspect of water quality by measuring the water's biochemical oxygen demand, or the amount of O
2 needed to restore it to a normal concentration.

Where on Earth is free oxygen found?

  • Ground Truth Answers: waterin solution in the world's water bodiesthe world's water bodies

  • Prediction:

At what temperatures is O2 more soluble?

  • Ground Truth Answers: lowerlowerlowerlowerlower temperatures

  • Prediction:

Why do polar water bodies support a higher amount of life?

  • Ground Truth Answers: higher oxygen contenthigher oxygen contenthigher oxygen contenthigher oxygen contentdue to their higher oxygen content

  • Prediction:

Pollution of water by nitrates and phosphates will encourage the growth of what?

  • Ground Truth Answers: algaealgaealgaealgaealgae

  • Prediction:

What measurement do scientists used to determine the quality of water?

  • Ground Truth Answers: biochemical oxygen demandbiochemical oxygen demandmeasuring the water's biochemical oxygen demandbiochemical oxygen demandmeasuring the water's biochemical oxygen demand

  • Prediction:

Free oxygen gas was almost nonexistent in Earth's atmosphere before photosynthetic archaea and bacteria evolved, probably about 3.5 billion years ago. Free oxygen first appeared in significant quantities during the Paleoproterozoic eon (between 3.0 and 2.3 billion years ago). For the first billion years, any free oxygen produced by these organisms combined with dissolved iron in the oceans to form banded iron formations. When such oxygen sinks became saturated, free oxygen began to outgas from the oceans 3–2.7 billion years ago, reaching 10% of its present level around 1.7 billion years ago.

When did photosynthetic organisms evolve on Earth?

  • Ground Truth Answers: 3.5 billion years agoabout 3.5 billion years agoabout 3.5 billion years ago3.5 billion years agoabout 3.5 billion years ago

  • Prediction:

During which eon did free oxygen begin appearing in quantity?

  • Ground Truth Answers: PaleoproterozoicPaleoproterozoicPaleoproterozoicPaleoproterozoicthe Paleoproterozoic eon

  • Prediction:

At first, what did oxygen and iron combine to form?

  • Ground Truth Answers: banded iron formationsbanded iron formationsbanded iron formationsbanded iron formationsbanded iron

  • Prediction:

How long ago did oxygen reach 10% of its present level?

  • Ground Truth Answers: 1.7 billion years ago1.7 billion years ago1.7 billion years ago1.7 billion years agoaround 1.7 billion years ago

  • Prediction:

When did oxygen begin to move from the oceans to the atmosphere?

  • Ground Truth Answers: 3–2.7 billion years ago3–2.7 billion years ago3–2.7 billion years ago3–2.7 billion years ago3–2.7 billion years ago

  • Prediction:

The unusually high concentration of oxygen gas on Earth is the result of the oxygen cycle. This biogeochemical cycle describes the movement of oxygen within and between its three main reservoirs on Earth: the atmosphere, the biosphere, and the lithosphere. The main driving factor of the oxygen cycle is photosynthesis, which is responsible for modern Earth's atmosphere. Photosynthesis releases oxygen into the atmosphere, while respiration and decay remove it from the atmosphere. In the present equilibrium, production and consumption occur at the same rate of roughly 1/2000th of the entire atmospheric oxygen per year.

What produces the high levels of oxygen on Earth?

  • Ground Truth Answers: oxygen cyclethe oxygen cycleoxygen cycleoxygen cyclethe oxygen cycle

  • Prediction:

What type of process is the oxygen cycle?

  • Ground Truth Answers: biogeochemicalbiogeochemicalbiogeochemicalbiogeochemical cyclebiogeochemical

  • Prediction:

In how many places is oxygen stored in its cycle?

  • Ground Truth Answers: threethreethreethree main reservoirsthree

  • Prediction:

What process is responsible for the planet's oxygen content?

  • Ground Truth Answers: photosynthesisphotosynthesisphotosynthesisphotosynthesisphotosynthesis

  • Prediction:

What does photosynthesis release into the Earth's atmosphere?

  • Ground Truth Answers: oxygenoxygenoxygenoxygenoxygen

  • Prediction:

The other major method of producing O
2 gas involves passing a stream of clean, dry air through one bed of a pair of identical zeolite molecular sieves, which absorbs the nitrogen and delivers a gas stream that is 90% to 93% O
2. Simultaneously, nitrogen gas is released from the other nitrogen-saturated zeolite bed, by reducing the chamber operating pressure and diverting part of the oxygen gas from the producer bed through it, in the reverse direction of flow. After a set cycle time the operation of the two beds is interchanged, thereby allowing for a continuous supply of gaseous oxygen to be pumped through a pipeline. This is known as pressure swing adsorption. Oxygen gas is increasingly obtained by these non-cryogenic technologies (see also the related vacuum swing adsorption).

What mechanism can be used to make oxygen?

  • Ground Truth Answers: zeolite molecular sieveszeolite molecular sievespassing a stream of clean, dry air through one bed of a pair of identical zeolite molecular sievespassing a stream of clean, dry air through one bed of a pair of identical zeolite molecular sieves, which absorbs the nitrogenpassing a stream of clean, dry air through one bed of a pair of identical zeolite molecular sieves

  • Prediction:

What percentage of oxygen will a zeolite sieve produce?

  • Ground Truth Answers: 90% to 93%90% to 93%90% to 93%90% to 93%90% to 93%

  • Prediction:

While producing oxygen, what gas does a zeolite sieve absorb?

  • Ground Truth Answers: nitrogennitrogennitrogennitrogennitrogen

  • Prediction:

What type of technology is the non organic separating of gases?

  • Ground Truth Answers: non-cryogenicnon-cryogenicnon-cryogenicnon-cryogenicnon-cryogenic

  • Prediction:

How much is the sieve method of gas production used?

  • Ground Truth Answers: major methodincreasinglymajor methodincreasingly

  • Prediction:

Oxygen gas can also be produced through electrolysis of water into molecular oxygen and hydrogen. DC electricity must be used: if AC is used, the gases in each limb consist of hydrogen and oxygen in the explosive ratio 2:1. Contrary to popular belief, the 2:1 ratio observed in the DC electrolysis of acidified water does not prove that the empirical formula of water is H2O unless certain assumptions are made about the molecular formulae of hydrogen and oxygen themselves. A similar method is the electrocatalytic O
2 evolution from oxides and oxoacids. Chemical catalysts can be used as well, such as in chemical oxygen generators or oxygen candles that are used as part of the life-support equipment on submarines, and are still part of standard equipment on commercial airliners in case of depressurization emergencies. Another air separation technology involves forcing air to dissolve through ceramic membranes based on zirconium dioxide by either high pressure or an electric current, to produce nearly pure O
2 gas.

Electrolysis of what can be used to produce oxygen and hydrogen?

  • Ground Truth Answers: waterwaterwaterwater

  • Prediction:

What does the electrolysis of water produce?

  • Ground Truth Answers: oxygen and hydrogenoxygen and hydrogenmolecular oxygen and hydrogenmolecular oxygen and hydrogenOxygen gas

  • Prediction:

What type of electric current is needed for electrolysis?

  • Ground Truth Answers: DCDC electricityDCDC electricity

  • Prediction:

What is the source of oxygen production through electrocatalytic means?

  • Ground Truth Answers: oxides and oxoacidsoxides and oxoacidsoxides and oxoacidsoxides and oxoacidsoxides and oxoacids

  • Prediction:

What other catalysts can be used to produce oxygen?

  • Ground Truth Answers: ChemicalChemicalChemicalchemical oxygen generators or oxygen candlesChemical

  • Prediction:

Oxygen, as a supposed mild euphoric, has a history of recreational use in oxygen bars and in sports. Oxygen bars are establishments, found in Japan, California, and Las Vegas, Nevada since the late 1990s that offer higher than normal O
2 exposure for a fee. Professional athletes, especially in American football, also sometimes go off field between plays to wear oxygen masks in order to get a "boost" in performance. The pharmacological effect is doubtful; a placebo effect is a more likely explanation. Available studies support a performance boost from enriched O
2 mixtures only if they are breathed during aerobic exercise.

As a euphoric how is oxygen used in bars?

  • Ground Truth Answers: recreationalrecreationalrecreational

  • Prediction:

What is the effect on humans of oxygen?

  • Ground Truth Answers: mild euphorica supposed mild euphorica supposed mild euphoriceuphoric

  • Prediction:

What do professional athletes seek to boost from breathing oxygen?

  • Ground Truth Answers: performanceperformanceperformanceperformancea "boost" in performance

  • Prediction:

What is the most likely effect of breathing oxygen?

  • Ground Truth Answers: placeboplaceboplaceboa placebo effectplacebo

  • Prediction:

What type of exercise does research show receives a boost in performance from oxygen?

  • Ground Truth Answers: aerobicaerobicaerobicaerobicaerobic exercise

  • Prediction:

Hyperbaric (high-pressure) medicine uses special oxygen chambers to increase the partial pressure of O
2 around the patient and, when needed, the medical staff. Carbon monoxide poisoning, gas gangrene, and decompression sickness (the 'bends') are sometimes treated using these devices. Increased O
2 concentration in the lungs helps to displace carbon monoxide from the heme group of hemoglobin. Oxygen gas is poisonous to the anaerobic bacteria that cause gas gangrene, so increasing its partial pressure helps kill them. Decompression sickness occurs in divers who decompress too quickly after a dive, resulting in bubbles of inert gas, mostly nitrogen and helium, forming in their blood. Increasing the pressure of O
2 as soon as possible is part of the treatment.

What device is used to treat various conditions such as carbon monoxide poisoning?

  • Ground Truth Answers: Hyperbaric (high-pressure) medicinespecial oxygen chambersoxygen chambersoxygen chambersoxygen chambers

  • Prediction:

What does increased oxygen concentrations in the patient's lungs displace?

  • Ground Truth Answers: carbon monoxidecarbon monoxidecarbon monoxidecarbon monoxidecarbon monoxide

  • Prediction:

To what pathogen that causes gas gangrene is oxygen poisonous?

  • Ground Truth Answers: anaerobic bacteriaanaerobic bacteriaanaerobic bacteriaanaerobic bacteriaanaerobic bacteria

  • Prediction:

What occurs after a dive in which a diver decompresses too quickly?

  • Ground Truth Answers: Decompression sicknessbubbles of inert gas, mostly nitrogen and helium, forming in their bloodDecompression sicknessdecompression sickness (the 'bends')Decompression sickness

  • Prediction:

Uptake of O
2 from the air is the essential purpose of respiration, so oxygen supplementation is used in medicine. Treatment not only increases oxygen levels in the patient's blood, but has the secondary effect of decreasing resistance to blood flow in many types of diseased lungs, easing work load on the heart. Oxygen therapy is used to treat emphysema, pneumonia, some heart disorders (congestive heart failure), some disorders that cause increased pulmonary artery pressure, and any disease that impairs the body's ability to take up and use gaseous oxygen.

What medical treatment is used to benefit patients with hearth and lung disorders?

  • Ground Truth Answers: Oxygen therapyOxygen therapyOxygen therapyOxygen therapyOxygen therapy

  • Prediction:

By decreasing resistance to blood flow in the lungs, what organ's workload can be eased?

  • Ground Truth Answers: heartthe heartheartthe heartheart

  • Prediction:

What medical treatment is used to increase oxygen uptake in a patient?

  • Ground Truth Answers: oxygen supplementationoxygen supplementationoxygen supplementationOxygen therapyOxygen therapy

  • Prediction:

In what process is the uptake from oxygen necessary?

  • Ground Truth Answers: respirationrespirationrespirationrespirationrespiration

  • Prediction:

What does oxygen therapy promote the body to take up?

  • Ground Truth Answers: gaseous oxygen.gaseous oxygengaseous oxygenoxygengaseous oxygen

  • Prediction:

Due to its electronegativity, oxygen forms chemical bonds with almost all other elements to give corresponding oxides. The surface of most metals, such as aluminium and titanium, are oxidized in the presence of air and become coated with a thin film of oxide that passivates the metal and slows further corrosion. Many oxides of the transition metals are non-stoichiometric compounds, with slightly less metal than the chemical formula would show. For example, the mineral FeO (wüstite) is written as Fe
1 − xO, where x is usually around 0.05.

What characteristic of oxygen causes it to form bonds with other elements?

  • Ground Truth Answers: electronegativityelectronegativityelectronegativityelectronegativityelectronegativity

  • Prediction:

What is usual form of oxygen bound compounds?

  • Ground Truth Answers: oxidesoxidesoxidesoxidesoxides

  • Prediction:

What is the mineral wustite?

  • Ground Truth Answers: FeOFeOFeOFeOFeO

  • Prediction:

What does oxygen cause to form on metals?

  • Ground Truth Answers: oxidea thin film of oxidea thin film of oxideoxidea thin film of oxide

  • Prediction:

What does the film of oxide on metals delay?

  • Ground Truth Answers: corrosionfurther corrosionfurther corrosionfurther corrosioncorrosion

  • Prediction:

People who climb mountains or fly in non-pressurized fixed-wing aircraft sometimes have supplemental O
2 supplies.[h] Passengers traveling in (pressurized) commercial airplanes have an emergency supply of O
2 automatically supplied to them in case of cabin depressurization. Sudden cabin pressure loss activates chemical oxygen generators above each seat, causing oxygen masks to drop. Pulling on the masks "to start the flow of oxygen" as cabin safety instructions dictate, forces iron filings into the sodium chlorate inside the canister. A steady stream of oxygen gas is then produced by the exothermic reaction.

What event would necessitate airline passengers to need a supplemental supply of oxygen?

  • Ground Truth Answers: cabin depressurizationcabin depressurizationcabin depressurizationcabin depressurizationdepressurization

  • Prediction:

What is the type of oxygen production for emergency oxygen in airlines?

  • Ground Truth Answers: chemicalchemical oxygenchemicalchemical oxygen generatorschemical

  • Prediction:

What type of reaction is present in the emergency oxygen generator of an airplane?

  • Ground Truth Answers: exothermicexothermicexothermicexothermicexothermic reaction

  • Prediction:

What gas does the airline exothermic reaction produce?

  • Ground Truth Answers: oxygen gasoxygenoxygenoxygenoxygen

  • Prediction:

Oxygen storage methods include high pressure oxygen tanks, cryogenics and chemical compounds. For reasons of economy, oxygen is often transported in bulk as a liquid in specially insulated tankers, since one liter of liquefied oxygen is equivalent to 840 liters of gaseous oxygen at atmospheric pressure and 20 °C (68 °F). Such tankers are used to refill bulk liquid oxygen storage containers, which stand outside hospitals and other institutions with a need for large volumes of pure oxygen gas. Liquid oxygen is passed through heat exchangers, which convert the cryogenic liquid into gas before it enters the building. Oxygen is also stored and shipped in smaller cylinders containing the compressed gas; a form that is useful in certain portable medical applications and oxy-fuel welding and cutting.

What do oxygen tanks, cryogenics, and chemical compounds serve as for oxygen?

  • Ground Truth Answers: storagestoragestorage methodsstoragestorage methods

  • Prediction:

By what means is bulk oxygen shipped?

  • Ground Truth Answers: insulated tankersinsulated tankersinsulated tankersspecially insulated tankers

  • Prediction:

In what state is oxygen shipped in bulk?

  • Ground Truth Answers: liquidas a liquidliquidas a liquid in specially insulated tankers

  • Prediction:

In what form is oxygen transported in smaller containers?

  • Ground Truth Answers: compressed gascompressed gascompressed gas;compressed gascompressed gas

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What type of organization would need large quantities of pure oxygen?

  • Ground Truth Answers: hospitalshospitalshospitalshospitalshospitals

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Among the most important classes of organic compounds that contain oxygen are (where "R" is an organic group): alcohols (R-OH); ethers (R-O-R); ketones (R-CO-R); aldehydes (R-CO-H); carboxylic acids (R-COOH); esters (R-COO-R); acid anhydrides (R-CO-O-CO-R); and amides (R-C(O)-NR
2). There are many important organic solvents that contain oxygen, including: acetone, methanol, ethanol, isopropanol, furan, THF, diethyl ether, dioxane, ethyl acetate, DMF, DMSO, acetic acid, and formic acid. Acetone ((CH
3)
2CO) and phenol (C
6H
5OH) are used as feeder materials in the synthesis of many different substances. Other important organic compounds that contain oxygen are: glycerol, formaldehyde, glutaraldehyde, citric acid, acetic anhydride, and acetamide. Epoxides are ethers in which the oxygen atom is part of a ring of three atoms.

What type of compounds such as acetone,contain oxygen?

  • Ground Truth Answers: organic solventsorganic solventsorganic solventssolventsorganic solvents

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In what group of compounds is oxygen a necessary part?

  • Ground Truth Answers: organic compoundsorganicsolventsorganic solvents

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What function do compounds like phenol and acetone serve in the manufacture of many other substances?

  • Ground Truth Answers: feeder materialsas feeder materialsfeeder materialsfeeder materialsas feeder materials

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In what compound is oxygen part of a ring arrangement?

  • Ground Truth Answers: EpoxidesEpoxidesEpoxidesEpoxidesEpoxides

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How are the compounds that contain oxygen considered in commerce?

  • Ground Truth Answers: importantimportantimportantimportant

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The element is found in almost all biomolecules that are important to (or generated by) life. Only a few common complex biomolecules, such as squalene and the carotenes, contain no oxygen. Of the organic compounds with biological relevance, carbohydrates contain the largest proportion by mass of oxygen. All fats, fatty acids, amino acids, and proteins contain oxygen (due to the presence of carbonyl groups in these acids and their ester residues). Oxygen also occurs in phosphate (PO3−
4) groups in the biologically important energy-carrying molecules ATP and ADP, in the backbone and the purines (except adenine) and pyrimidines of RNA and DNA, and in bones as calcium phosphate and hydroxylapatite.

In what type of molecules are oxygen found?

  • Ground Truth Answers: biomoleculesbiomoleculesbiomoleculesbiomoleculesalmost all biomolecules that are important to (or generated by) life

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How many biomolecules contain no oxygen?

  • Ground Truth Answers: Only a fewOnly a fewa fewOnly a fewa few

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Which organic compounds contain the greatest amount of oxygen by mass?

  • Ground Truth Answers: carbohydratescarbohydratescarbohydratescarbohydratescarbohydrates

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Besides fats, fatty acids, and amino acids,what other organic compounds contain oxygen?

  • Ground Truth Answers: proteinsproteinsproteinsproteinsproteins

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In what calcium containing body part is oxygen a part?

  • Ground Truth Answers: bonesbonesbonesbonesbones

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Oxygen toxicity to the lungs and central nervous system can also occur in deep scuba diving and surface supplied diving. Prolonged breathing of an air mixture with an O
2 partial pressure more than 60 kPa can eventually lead to permanent pulmonary fibrosis. Exposure to a O
2 partial pressures greater than 160 kPa (about 1.6 atm) may lead to convulsions (normally fatal for divers). Acute oxygen toxicity (causing seizures, its most feared effect for divers) can occur by breathing an air mixture with 21% O
2 at 66 m or more of depth; the same thing can occur by breathing 100% O
2 at only 6 m.

What health condition can deep sea diving cause?

  • Ground Truth Answers: Oxygen toxicityOxygen toxicityOxygen toxicityOxygen toxicityOxygen toxicity to the lungs and central nervous system

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To what can the use of prolonged breathing of oxygen at 60 kPa lead?

  • Ground Truth Answers: pulmonary fibrosispermanent pulmonary fibrosispermanent pulmonary fibrosispermanent pulmonary fibrosispulmonary fibrosis

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Pressures greater than what can lead to convulsions?

  • Ground Truth Answers: 160 kPa160 kPa160 kPa (about 1.6 atm)160 kPa (about 1.6 atm)160 kPa

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What is the most feared condition that divers want to avoid?

  • Ground Truth Answers: Acute oxygen toxicityAcute oxygen toxicityseizuresseizuresseizures

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What physical condition can acute oxygen toxicity cause?

  • Ground Truth Answers: seizuresseizuresseizuresseizuresseizures

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Breathing pure O
2 in space applications, such as in some modern space suits, or in early spacecraft such as Apollo, causes no damage due to the low total pressures used. In the case of spacesuits, the O
2 partial pressure in the breathing gas is, in general, about 30 kPa (1.4 times normal), and the resulting O
2 partial pressure in the astronaut's arterial blood is only marginally more than normal sea-level O
2 partial pressure (for more information on this, see space suit and arterial blood gas).

Why is breathing oxygen in space craft not dangerous to health?

  • Ground Truth Answers: low total pressureslow total pressures usedlow total pressureslow total pressuresthe low total pressures used

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What is the oxygen partial pressure of space suits?

  • Ground Truth Answers: 30 kPaabout 30 kPaabout 30 kPa30 kPaabout 30 kPa (1.4 times normal)

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How much of normal is the oxygen breathed in space suits?

  • Ground Truth Answers: 1.4 times normal1.4 times1.4 times1.4 times normal1.4 times normal

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How much damage does breathing oxygen in space conditions cause?

  • Ground Truth Answers: no damageno damagenonono damage

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What si the comparison to sea level with the oxygen level in space suits?

  • Ground Truth Answers: only marginally moremarginally more than normalmarginally moremarginally moreonly marginally more

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Oxygen gas (O
2) can be toxic at elevated partial pressures, leading to convulsions and other health problems.[j] Oxygen toxicity usually begins to occur at partial pressures more than 50 kilopascals (kPa), equal to about 50% oxygen composition at standard pressure or 2.5 times the normal sea-level O
2 partial pressure of about 21 kPa. This is not a problem except for patients on mechanical ventilators, since gas supplied through oxygen masks in medical applications is typically composed of only 30%–50% O
2 by volume (about 30 kPa at standard pressure). (although this figure also is subject to wide variation, depending on type of mask).

When can oxygen gas produce a toxic condition?

  • Ground Truth Answers: at elevated partial pressureselevated partial pressuresat elevated partial pressuresat elevated partial pressureselevated partial pressures

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At what point does oxygen toxicity begin to happen?

  • Ground Truth Answers: 50 kilopascalsat partial pressures more than 50 kilopascals50 kilopascalsmore than 50 kilopascalsat partial pressures more than 50 kilopascals

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To what is 50 kilopascals equal?

  • Ground Truth Answers: 50% oxygenabout 50% oxygen composition at standard pressureabout 50% oxygen composition at standard pressure

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What medical appliance can be a concern for oxygen toxicity?

  • Ground Truth Answers: mechanical ventilatorsmechanical ventilatorsmechanical ventilatorsoxygen masksmechanical ventilators

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What percentage of oxygen is usually supplied by a medical mask?

  • Ground Truth Answers: 30%–50%30%–50%30%–50%30%–50%

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