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56e1944ae3433e1400422fdc
Hydrogen
Throughout the universe, hydrogen is mostly found in the atomic and plasma states whose properties are quite different from molecular hydrogen. As a plasma, hydrogen's electron and proton are not bound together, resulting in very high electrical conductivity and high emissivity (producing the light from the Sun and oth...
In what states is hydrogen mostly found in the universe?
{ "text": [ "atomic and plasma" ], "answer_start": [ 57 ] }
56e1944ae3433e1400422fdd
Hydrogen
Throughout the universe, hydrogen is mostly found in the atomic and plasma states whose properties are quite different from molecular hydrogen. As a plasma, hydrogen's electron and proton are not bound together, resulting in very high electrical conductivity and high emissivity (producing the light from the Sun and oth...
Hydrogens electron and proton are not bound together in what state?
{ "text": [ "plasma" ], "answer_start": [ 68 ] }
56e1944ae3433e1400422fdf
Hydrogen
Throughout the universe, hydrogen is mostly found in the atomic and plasma states whose properties are quite different from molecular hydrogen. As a plasma, hydrogen's electron and proton are not bound together, resulting in very high electrical conductivity and high emissivity (producing the light from the Sun and oth...
in the interstellar medium, what state is hydrogen in?
{ "text": [ "neutral atomic state" ], "answer_start": [ 559 ] }
56e1944ae3433e1400422fe0
Hydrogen
Throughout the universe, hydrogen is mostly found in the atomic and plasma states whose properties are quite different from molecular hydrogen. As a plasma, hydrogen's electron and proton are not bound together, resulting in very high electrical conductivity and high emissivity (producing the light from the Sun and oth...
The neutral hydrogen found in the damped Lyman-alpha systems dominates what?
{ "text": [ "cosmological baryonic density of the Universe" ], "answer_start": [ 712 ] }
56e1954fcd28a01900c679dd
Hydrogen
Under ordinary conditions on Earth, elemental hydrogen exists as the diatomic gas, H2. However, hydrogen gas is very rare in the Earth's atmosphere (1 ppm by volume) because of its light weight, which enables it to escape from Earth's gravity more easily than heavier gases. However, hydrogen is the third most abundant ...
How abundant is hydrogen on the earths surface?
{ "text": [ "third most abundant" ], "answer_start": [ 300 ] }
56e1954fcd28a01900c679df
Hydrogen
Under ordinary conditions on Earth, elemental hydrogen exists as the diatomic gas, H2. However, hydrogen gas is very rare in the Earth's atmosphere (1 ppm by volume) because of its light weight, which enables it to escape from Earth's gravity more easily than heavier gases. However, hydrogen is the third most abundant ...
what produces hydrogen gas?
{ "text": [ "bacteria and algae" ], "answer_start": [ 458 ] }
56e1963acd28a01900c679e5
Hydrogen
A molecular form called protonated molecular hydrogen (H+ 3) is found in the interstellar medium, where it is generated by ionization of molecular hydrogen from cosmic rays. This charged ion has also been observed in the upper atmosphere of the planet Jupiter. The ion is relatively stable in the environment of outer sp...
What molecular form is found in the interstellar medium?
{ "text": [ "protonated molecular hydrogen" ], "answer_start": [ 24 ] }
56e1963acd28a01900c679e7
Hydrogen
A molecular form called protonated molecular hydrogen (H+ 3) is found in the interstellar medium, where it is generated by ionization of molecular hydrogen from cosmic rays. This charged ion has also been observed in the upper atmosphere of the planet Jupiter. The ion is relatively stable in the environment of outer sp...
What generates protonated molecular hydrogen?
{ "text": [ "ionization of molecular hydrogen from cosmic rays" ], "answer_start": [ 123 ] }
56e1963acd28a01900c679e8
Hydrogen
A molecular form called protonated molecular hydrogen (H+ 3) is found in the interstellar medium, where it is generated by ionization of molecular hydrogen from cosmic rays. This charged ion has also been observed in the upper atmosphere of the planet Jupiter. The ion is relatively stable in the environment of outer sp...
On what planet can you find protonated molecular hydrogen?
{ "text": [ "Jupiter" ], "answer_start": [ 252 ] }
56e1963acd28a01900c679e9
Hydrogen
A molecular form called protonated molecular hydrogen (H+ 3) is found in the interstellar medium, where it is generated by ionization of molecular hydrogen from cosmic rays. This charged ion has also been observed in the upper atmosphere of the planet Jupiter. The ion is relatively stable in the environment of outer sp...
In what way can Neutral triatomic hydrogen exist?
{ "text": [ "excited form" ], "answer_start": [ 543 ] }
56e196cfcd28a01900c679f0
Hydrogen
H 2 is produced in chemistry and biology laboratories, often as a by-product of other reactions; in industry for the hydrogenation of unsaturated substrates; and in nature as a means of expelling reducing equivalents in biochemical reactions.
How does nature produce H2?
{ "text": [ "expelling reducing equivalents in biochemical reactions" ], "answer_start": [ 186 ] }
56e196cfcd28a01900c679f1
Hydrogen
H 2 is produced in chemistry and biology laboratories, often as a by-product of other reactions; in industry for the hydrogenation of unsaturated substrates; and in nature as a means of expelling reducing equivalents in biochemical reactions.
How do labs produce H2?
{ "text": [ "by-product of other reactions" ], "answer_start": [ 66 ] }
56e197a3cd28a01900c67a00
Hydrogen
The electrolysis of water is a simple method of producing hydrogen. A low voltage current is run through the water, and gaseous oxygen forms at the anode while gaseous hydrogen forms at the cathode. Typically the cathode is made from platinum or another inert metal when producing hydrogen for storage. If, however, the ...
What is an easy way to produce hydrogen?
{ "text": [ "electrolysis of water" ], "answer_start": [ 4 ] }
56e197a3cd28a01900c67a02
Hydrogen
The electrolysis of water is a simple method of producing hydrogen. A low voltage current is run through the water, and gaseous oxygen forms at the anode while gaseous hydrogen forms at the cathode. Typically the cathode is made from platinum or another inert metal when producing hydrogen for storage. If, however, the ...
Where does the gaseous oxygen form at?
{ "text": [ "anode" ], "answer_start": [ 148 ] }
56e197a3cd28a01900c67a03
Hydrogen
The electrolysis of water is a simple method of producing hydrogen. A low voltage current is run through the water, and gaseous oxygen forms at the anode while gaseous hydrogen forms at the cathode. Typically the cathode is made from platinum or another inert metal when producing hydrogen for storage. If, however, the ...
Where does the gaseous hydrogen form at?
{ "text": [ "cathode" ], "answer_start": [ 190 ] }
56e19878cd28a01900c67a14
Hydrogen
An alloy of aluminium and gallium in pellet form added to water can be used to generate hydrogen. The process also produces alumina, but the expensive gallium, which prevents the formation of an oxide skin on the pellets, can be re-used. This has important potential implications for a hydrogen economy, as hydrogen can ...
When you combine an alloy of alluminum and gallium to water, what do you get?
{ "text": [ "hydrogen" ], "answer_start": [ 88 ] }
56e19878cd28a01900c67a15
Hydrogen
An alloy of aluminium and gallium in pellet form added to water can be used to generate hydrogen. The process also produces alumina, but the expensive gallium, which prevents the formation of an oxide skin on the pellets, can be re-used. This has important potential implications for a hydrogen economy, as hydrogen can ...
What else can it produce?
{ "text": [ "alumina" ], "answer_start": [ 124 ] }
56e19878cd28a01900c67a16
Hydrogen
An alloy of aluminium and gallium in pellet form added to water can be used to generate hydrogen. The process also produces alumina, but the expensive gallium, which prevents the formation of an oxide skin on the pellets, can be re-used. This has important potential implications for a hydrogen economy, as hydrogen can ...
What can be reused after the formation?
{ "text": [ "the expensive gallium" ], "answer_start": [ 137 ] }
56e1993fcd28a01900c67a1c
Hydrogen
Hydrogen can be prepared in several different ways, but economically the most important processes involve removal of hydrogen from hydrocarbons. Commercial bulk hydrogen is usually produced by the steam reforming of natural gas. At high temperatures (1000–1400 K, 700–1100 °C or 1300–2000 °F), steam (water vapor) reacts...
The most economical way to prepare hydrogen involves removing it from what?
{ "text": [ "hydrocarbons" ], "answer_start": [ 131 ] }
56e1993fcd28a01900c67a1e
Hydrogen
Hydrogen can be prepared in several different ways, but economically the most important processes involve removal of hydrogen from hydrocarbons. Commercial bulk hydrogen is usually produced by the steam reforming of natural gas. At high temperatures (1000–1400 K, 700–1100 °C or 1300–2000 °F), steam (water vapor) reacts...
What temperature is needed for steam to react with methane?
{ "text": [ "1000–1400 K, 700–1100 °C or 1300–2000 °F" ], "answer_start": [ 251 ] }
56e19ab0e3433e1400423000
Hydrogen
This reaction is favored at low pressures but is nonetheless conducted at high pressures (2.0 MPa, 20 atm or 600 inHg). This is because high-pressure H 2 is the most marketable product and Pressure Swing Adsorption (PSA) purification systems work better at higher pressures. The product mixture is known as "synthesis ga...
At what pressure does PSA work best in?
{ "text": [ "high pressures" ], "answer_start": [ 74 ] }
56e19ab0e3433e1400423001
Hydrogen
This reaction is favored at low pressures but is nonetheless conducted at high pressures (2.0 MPa, 20 atm or 600 inHg). This is because high-pressure H 2 is the most marketable product and Pressure Swing Adsorption (PSA) purification systems work better at higher pressures. The product mixture is known as "synthesis ga...
What is synthesis gas used for?
{ "text": [ "production of methanol" ], "answer_start": [ 366 ] }
56e19ab0e3433e1400423002
Hydrogen
This reaction is favored at low pressures but is nonetheless conducted at high pressures (2.0 MPa, 20 atm or 600 inHg). This is because high-pressure H 2 is the most marketable product and Pressure Swing Adsorption (PSA) purification systems work better at higher pressures. The product mixture is known as "synthesis ga...
Besides methane, what else can be used to produce synthesis gas?
{ "text": [ "Hydrocarbons" ], "answer_start": [ 412 ] }
56e19b21e3433e140042300a
Hydrogen
Consequently, steam reforming typically employs an excess of H 2O. Additional hydrogen can be recovered from the steam by use of carbon monoxide through the water gas shift reaction, especially with an iron oxide catalyst. This reaction is also a common industrial source of carbon dioxide:
How can it be recovered through steam?
{ "text": [ "use of carbon monoxide through the water gas shift reaction" ], "answer_start": [ 122 ] }
56e19ba6e3433e1400423011
Hydrogen
Hydrogen is sometimes produced and consumed in the same industrial process, without being separated. In the Haber process for the production of ammonia, hydrogen is generated from natural gas. Electrolysis of brine to yield chlorine also produces hydrogen as a co-product.
When hydrogen is generated from natural gas, what des it produce?
{ "text": [ "ammonia" ], "answer_start": [ 144 ] }
56e19ba6e3433e1400423012
Hydrogen
Hydrogen is sometimes produced and consumed in the same industrial process, without being separated. In the Haber process for the production of ammonia, hydrogen is generated from natural gas. Electrolysis of brine to yield chlorine also produces hydrogen as a co-product.
How is hydrogen produced as a co product?
{ "text": [ "Electrolysis of brine to yield chlorine" ], "answer_start": [ 193 ] }
56e19c6ee3433e1400423022
Hydrogen
There are more than 200 thermochemical cycles which can be used for water splitting, around a dozen of these cycles such as the iron oxide cycle, cerium(IV) oxide–cerium(III) oxide cycle, zinc zinc-oxide cycle, sulfur-iodine cycle, copper-chlorine cycle and hybrid sulfur cycle are under research and in testing phase to...
What are labs trying to produce hydrogen from?
{ "text": [ "solar energy and water" ], "answer_start": [ 543 ] }
56e19c6ee3433e1400423023
Hydrogen
There are more than 200 thermochemical cycles which can be used for water splitting, around a dozen of these cycles such as the iron oxide cycle, cerium(IV) oxide–cerium(III) oxide cycle, zinc zinc-oxide cycle, sulfur-iodine cycle, copper-chlorine cycle and hybrid sulfur cycle are under research and in testing phase to...
What countries are testing this?
{ "text": [ "France, Germany, Greece, Japan, and the USA" ], "answer_start": [ 435 ] }
56e19cebe3433e1400423028
Hydrogen
Under anaerobic conditions, iron and steel alloys are slowly oxidized by the protons of water concomitantly reduced in molecular hydrogen (H 2). The anaerobic corrosion of iron leads first to the formation of ferrous hydroxide (green rust) and can be described by the following reaction:
What condition is iron and steel alloys slowly oxidized?
{ "text": [ "anaerobic" ], "answer_start": [ 6 ] }
56e19cebe3433e1400423029
Hydrogen
Under anaerobic conditions, iron and steel alloys are slowly oxidized by the protons of water concomitantly reduced in molecular hydrogen (H 2). The anaerobic corrosion of iron leads first to the formation of ferrous hydroxide (green rust) and can be described by the following reaction:
What does the anaerobic corrosion of iron lead to?
{ "text": [ "formation of ferrous hydroxide" ], "answer_start": [ 196 ] }
56e19cebe3433e140042302a
Hydrogen
Under anaerobic conditions, iron and steel alloys are slowly oxidized by the protons of water concomitantly reduced in molecular hydrogen (H 2). The anaerobic corrosion of iron leads first to the formation of ferrous hydroxide (green rust) and can be described by the following reaction:
What is another name for formation of ferrous hydroxide?
{ "text": [ "green rust" ], "answer_start": [ 228 ] }
56e19d84e3433e140042302e
Hydrogen
In its turn, under anaerobic conditions, the ferrous hydroxide (Fe(OH) 2 ) can be oxidized by the protons of water to form magnetite and molecular hydrogen. This process is described by the Schikorr reaction:
Under what condition can ferrous hydroxide be oxidized?
{ "text": [ "anaerobic" ], "answer_start": [ 19 ] }
56e19d84e3433e140042302f
Hydrogen
In its turn, under anaerobic conditions, the ferrous hydroxide (Fe(OH) 2 ) can be oxidized by the protons of water to form magnetite and molecular hydrogen. This process is described by the Schikorr reaction:
What does this process form?
{ "text": [ "magnetite and molecular hydrogen" ], "answer_start": [ 123 ] }
56e19d84e3433e1400423030
Hydrogen
In its turn, under anaerobic conditions, the ferrous hydroxide (Fe(OH) 2 ) can be oxidized by the protons of water to form magnetite and molecular hydrogen. This process is described by the Schikorr reaction:
What reaction describes this process?
{ "text": [ "Schikorr reaction" ], "answer_start": [ 190 ] }
56e19e9ccd28a01900c67a22
Hydrogen
In the absence of atmospheric oxygen (O 2), in deep geological conditions prevailing far away from Earth atmosphere, hydrogen (H 2) is produced during the process of serpentinization by the anaerobic oxidation by the water protons (H+) of the ferrous (Fe2+) silicate present in the crystal lattice of the fayalite (Fe 2S...
How is hydrogen produced when there is no atmospheric oxygen?
{ "text": [ "serpentinization by the anaerobic oxidation" ], "answer_start": [ 166 ] }
56e19e9ccd28a01900c67a23
Hydrogen
In the absence of atmospheric oxygen (O 2), in deep geological conditions prevailing far away from Earth atmosphere, hydrogen (H 2) is produced during the process of serpentinization by the anaerobic oxidation by the water protons (H+) of the ferrous (Fe2+) silicate present in the crystal lattice of the fayalite (Fe 2S...
Where do you find silicate?
{ "text": [ "crystal lattice of the fayalite" ], "answer_start": [ 282 ] }
56e19edbe3433e140042303e
Hydrogen
From all the fault gases formed in power transformers, hydrogen is the most common and is generated under most fault conditions; thus, formation of hydrogen is an early indication of serious problems in the transformer's life cycle.
What is the most common gas found in power tranformers?
{ "text": [ "hydrogen" ], "answer_start": [ 55 ] }
56e19fb6cd28a01900c67a26
Hydrogen
Large quantities of H 2 are needed in the petroleum and chemical industries. The largest application of H 2 is for the processing ("upgrading") of fossil fuels, and in the production of ammonia. The key consumers of H 2 in the petrochemical plant include hydrodealkylation, hydrodesulfurization, and hydrocracking. H 2 h...
Where are large quantities of H2 needed?
{ "text": [ "petroleum and chemical industries" ], "answer_start": [ 42 ] }
56e19fb6cd28a01900c67a28
Hydrogen
Large quantities of H 2 are needed in the petroleum and chemical industries. The largest application of H 2 is for the processing ("upgrading") of fossil fuels, and in the production of ammonia. The key consumers of H 2 in the petrochemical plant include hydrodealkylation, hydrodesulfurization, and hydrocracking. H 2 h...
What are the consumers of H2 in petrochemical plant?
{ "text": [ "hydrodealkylation, hydrodesulfurization, and hydrocracking" ], "answer_start": [ 255 ] }
56e1a1e1cd28a01900c67a36
Hydrogen
Hydrogen is highly soluble in many rare earth and transition metals and is soluble in both nanocrystalline and amorphous metals. Hydrogen solubility in metals is influenced by local distortions or impurities in the crystal lattice. These properties may be useful when hydrogen is purified by passage through hot palladiu...
Where is hydrogen highly soluble?
{ "text": [ "rare earth and transition metals" ], "answer_start": [ 35 ] }
56e1a1e1cd28a01900c67a37
Hydrogen
Hydrogen is highly soluble in many rare earth and transition metals and is soluble in both nanocrystalline and amorphous metals. Hydrogen solubility in metals is influenced by local distortions or impurities in the crystal lattice. These properties may be useful when hydrogen is purified by passage through hot palladiu...
Where can you find soluble hydrogen?
{ "text": [ "nanocrystalline and amorphous metals" ], "answer_start": [ 91 ] }
56e1a1e1cd28a01900c67a38
Hydrogen
Hydrogen is highly soluble in many rare earth and transition metals and is soluble in both nanocrystalline and amorphous metals. Hydrogen solubility in metals is influenced by local distortions or impurities in the crystal lattice. These properties may be useful when hydrogen is purified by passage through hot palladiu...
What influences hydrogens solubility in metals?
{ "text": [ "local distortions or impurities in the crystal lattice" ], "answer_start": [ 176 ] }
56e1a1e1cd28a01900c67a39
Hydrogen
Hydrogen is highly soluble in many rare earth and transition metals and is soluble in both nanocrystalline and amorphous metals. Hydrogen solubility in metals is influenced by local distortions or impurities in the crystal lattice. These properties may be useful when hydrogen is purified by passage through hot palladiu...
When are these useful?
{ "text": [ "when hydrogen is purified by passage through hot palladium disks" ], "answer_start": [ 263 ] }
56e1a28ee3433e140042304c
Hydrogen
Apart from its use as a reactant, H 2 has wide applications in physics and engineering. It is used as a shielding gas in welding methods such as atomic hydrogen welding. H2 is used as the rotor coolant in electrical generators at power stations, because it has the highest thermal conductivity of any gas. Liquid H2 is u...
Where else is H2 applied?
{ "text": [ "in physics and engineering" ], "answer_start": [ 60 ] }
56e1a28ee3433e140042304e
Hydrogen
Apart from its use as a reactant, H 2 has wide applications in physics and engineering. It is used as a shielding gas in welding methods such as atomic hydrogen welding. H2 is used as the rotor coolant in electrical generators at power stations, because it has the highest thermal conductivity of any gas. Liquid H2 is u...
How is H2 used in electrical generators at power stations?
{ "text": [ "as the rotor coolant" ], "answer_start": [ 181 ] }
56e1a28ee3433e140042304f
Hydrogen
Apart from its use as a reactant, H 2 has wide applications in physics and engineering. It is used as a shielding gas in welding methods such as atomic hydrogen welding. H2 is used as the rotor coolant in electrical generators at power stations, because it has the highest thermal conductivity of any gas. Liquid H2 is u...
Why is it used as the rotor coolant?
{ "text": [ "it has the highest thermal conductivity of any gas" ], "answer_start": [ 254 ] }
56e1a28ee3433e1400423050
Hydrogen
Apart from its use as a reactant, H 2 has wide applications in physics and engineering. It is used as a shielding gas in welding methods such as atomic hydrogen welding. H2 is used as the rotor coolant in electrical generators at power stations, because it has the highest thermal conductivity of any gas. Liquid H2 is u...
What research uses liquid H2?
{ "text": [ "cryogenic" ], "answer_start": [ 327 ] }
56e1a30ee3433e1400423056
Hydrogen
In more recent applications, hydrogen is used pure or mixed with nitrogen (sometimes called forming gas) as a tracer gas for minute leak detection. Applications can be found in the automotive, chemical, power generation, aerospace, and telecommunications industries. Hydrogen is an authorized food additive (E 949) that ...
Why would one use hydrogen mixed with nitrogen?
{ "text": [ "as a tracer gas for minute leak detection" ], "answer_start": [ 105 ] }
56e1a30ee3433e1400423057
Hydrogen
In more recent applications, hydrogen is used pure or mixed with nitrogen (sometimes called forming gas) as a tracer gas for minute leak detection. Applications can be found in the automotive, chemical, power generation, aerospace, and telecommunications industries. Hydrogen is an authorized food additive (E 949) that ...
What industries can you find these applications?
{ "text": [ "automotive, chemical, power generation, aerospace, and telecommunications" ], "answer_start": [ 181 ] }
56e1a30ee3433e1400423058
Hydrogen
In more recent applications, hydrogen is used pure or mixed with nitrogen (sometimes called forming gas) as a tracer gas for minute leak detection. Applications can be found in the automotive, chemical, power generation, aerospace, and telecommunications industries. Hydrogen is an authorized food additive (E 949) that ...
How is hydrogen used as a food additive?
{ "text": [ "allows food package leak testing" ], "answer_start": [ 320 ] }
56e1a3b2cd28a01900c67a40
Hydrogen
Hydrogen's rarer isotopes also each have specific applications. Deuterium (hydrogen-2) is used in nuclear fission applications as a moderator to slow neutrons, and in nuclear fusion reactions. Deuterium compounds have applications in chemistry and biology in studies of reaction isotope effects. Tritium (hydrogen-3), pr...
What isotope is used in nuclear fission?
{ "text": [ "Deuterium" ], "answer_start": [ 64 ] }
56e1a3b2cd28a01900c67a42
Hydrogen
Hydrogen's rarer isotopes also each have specific applications. Deuterium (hydrogen-2) is used in nuclear fission applications as a moderator to slow neutrons, and in nuclear fusion reactions. Deuterium compounds have applications in chemistry and biology in studies of reaction isotope effects. Tritium (hydrogen-3), pr...
Where is tritium produced?
{ "text": [ "nuclear reactors" ], "answer_start": [ 330 ] }
56e1a41ee3433e1400423070
Hydrogen
Hydrogen is commonly used in power stations as a coolant in generators due to a number of favorable properties that are a direct result of its light diatomic molecules. These include low density, low viscosity, and the highest specific heat and thermal conductivity of all gases.
How is hydrogen used at power stations?
{ "text": [ "as a coolant in generators" ], "answer_start": [ 44 ] }
56e1a498e3433e1400423076
Hydrogen
Hydrogen is not an energy resource, except in the hypothetical context of commercial nuclear fusion power plants using deuterium or tritium, a technology presently far from development. The Sun's energy comes from nuclear fusion of hydrogen, but this process is difficult to achieve controllably on Earth. Elemental hydr...
Is Hydrogen considered an energy resource?
{ "text": [ "not" ], "answer_start": [ 12 ] }
56e1a498e3433e1400423077
Hydrogen
Hydrogen is not an energy resource, except in the hypothetical context of commercial nuclear fusion power plants using deuterium or tritium, a technology presently far from development. The Sun's energy comes from nuclear fusion of hydrogen, but this process is difficult to achieve controllably on Earth. Elemental hydr...
Where does the sun get its energy from?
{ "text": [ "nuclear fusion of hydrogen" ], "answer_start": [ 214 ] }
56e1a498e3433e1400423078
Hydrogen
Hydrogen is not an energy resource, except in the hypothetical context of commercial nuclear fusion power plants using deuterium or tritium, a technology presently far from development. The Sun's energy comes from nuclear fusion of hydrogen, but this process is difficult to achieve controllably on Earth. Elemental hydr...
How does hydrogen function when it s burned?
{ "text": [ "energy carrier" ], "answer_start": [ 477 ] }
56e1a588cd28a01900c67a53
Hydrogen
The energy density per unit volume of both liquid hydrogen and compressed hydrogen gas at any practicable pressure is significantly less than that of traditional fuel sources, although the energy density per unit fuel mass is higher. Nevertheless, elemental hydrogen has been widely discussed in the context of energy, a...
What form of hydrogen has been discussed as a ussage for fuel?
{ "text": [ "elemental" ], "answer_start": [ 248 ] }
56e1a620cd28a01900c67a5b
Hydrogen
Hydrogen is employed to saturate broken ("dangling") bonds of amorphous silicon and amorphous carbon that helps stabilizing material properties. It is also a potential electron donor in various oxide materials, including ZnO, SnO2, CdO, MgO, ZrO2, HfO2, La2O3, Y2O3, TiO2, SrTiO3, LaAlO3, SiO2, Al2O3, ZrSiO4, HfSiO4, an...
How is hydrogen used in oxide materials?
{ "text": [ "a potential electron donor" ], "answer_start": [ 156 ] }
56e1a6d1cd28a01900c67a60
Hydrogen
H2 is a product of some types of anaerobic metabolism and is produced by several microorganisms, usually via reactions catalyzed by iron- or nickel-containing enzymes called hydrogenases. These enzymes catalyze the reversible redox reaction between H2 and its component two protons and two electrons. Creation of hydroge...
What enzymes are used to produce H2?
{ "text": [ "hydrogenases" ], "answer_start": [ 174 ] }
56e1a6d1cd28a01900c67a63
Hydrogen
H2 is a product of some types of anaerobic metabolism and is produced by several microorganisms, usually via reactions catalyzed by iron- or nickel-containing enzymes called hydrogenases. These enzymes catalyze the reversible redox reaction between H2 and its component two protons and two electrons. Creation of hydroge...
What is the natural cycle of hydrogen production and consumption by organisms called?
{ "text": [ "hydrogen cycle" ], "answer_start": [ 505 ] }
56e1a770e3433e140042307e
Hydrogen
Water splitting, in which water is decomposed into its component protons, electrons, and oxygen, occurs in the light reactions in all photosynthetic organisms. Some such organisms, including the alga Chlamydomonas reinhardtii and cyanobacteria, have evolved a second step in the dark reactions in which protons and elect...
What is the decomposition of water into its components called?
{ "text": [ "Water splitting" ], "answer_start": [ 0 ] }
56e1a770e3433e140042307f
Hydrogen
Water splitting, in which water is decomposed into its component protons, electrons, and oxygen, occurs in the light reactions in all photosynthetic organisms. Some such organisms, including the alga Chlamydomonas reinhardtii and cyanobacteria, have evolved a second step in the dark reactions in which protons and elect...
Where does water splitting occur?
{ "text": [ "in the light reactions in all photosynthetic organisms" ], "answer_start": [ 104 ] }
56e1a770e3433e1400423080
Hydrogen
Water splitting, in which water is decomposed into its component protons, electrons, and oxygen, occurs in the light reactions in all photosynthetic organisms. Some such organisms, including the alga Chlamydomonas reinhardtii and cyanobacteria, have evolved a second step in the dark reactions in which protons and elect...
What organisms can form H2 gas?
{ "text": [ "alga Chlamydomonas reinhardtii and cyanobacteria" ], "answer_start": [ 195 ] }
56e1a770e3433e1400423081
Hydrogen
Water splitting, in which water is decomposed into its component protons, electrons, and oxygen, occurs in the light reactions in all photosynthetic organisms. Some such organisms, including the alga Chlamydomonas reinhardtii and cyanobacteria, have evolved a second step in the dark reactions in which protons and elect...
How are these gases formed?
{ "text": [ "by specialized hydrogenases in the chloroplast" ], "answer_start": [ 352 ] }
56e1a815e3433e1400423088
Hydrogen
Hydrogen poses a number of hazards to human safety, from potential detonations and fires when mixed with air to being an asphyxiant in its pure, oxygen-free form. In addition, liquid hydrogen is a cryogen and presents dangers (such as frostbite) associated with very cold liquids. Hydrogen dissolves in many metals, and,...
What can hydrogen embrittlement lead to?
{ "text": [ "cracks and explosions" ], "answer_start": [ 426 ] }
56e1a8b5e3433e140042308e
Hydrogen
Even interpreting the hydrogen data (including safety data) is confounded by a number of phenomena. Many physical and chemical properties of hydrogen depend on the parahydrogen/orthohydrogen ratio (it often takes days or weeks at a given temperature to reach the equilibrium ratio, for which the data is usually given). ...
What do physical and chemical properties of hydrogen depend on?
{ "text": [ "the parahydrogen/orthohydrogen ratio" ], "answer_start": [ 160 ] }
56e1a8b5e3433e140042308f
Hydrogen
Even interpreting the hydrogen data (including safety data) is confounded by a number of phenomena. Many physical and chemical properties of hydrogen depend on the parahydrogen/orthohydrogen ratio (it often takes days or weeks at a given temperature to reach the equilibrium ratio, for which the data is usually given). ...
How long can it take to reach the equilibrium ratio?
{ "text": [ "days or weeks" ], "answer_start": [ 213 ] }
56e1a8b5e3433e1400423090
Hydrogen
Even interpreting the hydrogen data (including safety data) is confounded by a number of phenomena. Many physical and chemical properties of hydrogen depend on the parahydrogen/orthohydrogen ratio (it often takes days or weeks at a given temperature to reach the equilibrium ratio, for which the data is usually given). ...
What do Hydrogen detonation parameters depend on?
{ "text": [ "container geometry" ], "answer_start": [ 429 ] }
56e073cb7aa994140058e4ea
Space_Race
The Space Race was a 20th-century competition between two Cold War rivals, the Soviet Union (USSR) and the United States (US), for supremacy in spaceflight capability. It had its origins in the missile-based nuclear arms race between the two nations that occurred following World War II, enabled by captured German rocke...
On what date did the Space Race begin?
{ "text": [ "August 2, 1955" ], "answer_start": [ 702 ] }
56e073cb7aa994140058e4eb
Space_Race
The Space Race was a 20th-century competition between two Cold War rivals, the Soviet Union (USSR) and the United States (US), for supremacy in spaceflight capability. It had its origins in the missile-based nuclear arms race between the two nations that occurred following World War II, enabled by captured German rocke...
Sputnik 1 started orbiting on what date?
{ "text": [ "October 4, 1957" ], "answer_start": [ 990 ] }
56e073cb7aa994140058e4ec
Space_Race
The Space Race was a 20th-century competition between two Cold War rivals, the Soviet Union (USSR) and the United States (US), for supremacy in spaceflight capability. It had its origins in the missile-based nuclear arms race between the two nations that occurred following World War II, enabled by captured German rocke...
Who was the first person in space?
{ "text": [ "Yuri Gagarin" ], "answer_start": [ 1080 ] }
56e073cb7aa994140058e4ed
Space_Race
The Space Race was a 20th-century competition between two Cold War rivals, the Soviet Union (USSR) and the United States (US), for supremacy in spaceflight capability. It had its origins in the missile-based nuclear arms race between the two nations that occurred following World War II, enabled by captured German rocke...
What was the date that the first human reached space?
{ "text": [ "April 12, 1961" ], "answer_start": [ 1097 ] }
56e0796b231d4119001ac197
Space_Race
The Space Race can trace its origins to Germany, beginning in the 1930s and continuing during World War II when Nazi Germany researched and built operational ballistic missiles. Starting in the early 1930s, during the last stages of the Weimar Republic, German aerospace engineers experimented with liquid-fueled rockets...
Which war in history did the Space Race begin to take root?
{ "text": [ "World War II" ], "answer_start": [ 94 ] }
56e0796b231d4119001ac199
Space_Race
The Space Race can trace its origins to Germany, beginning in the 1930s and continuing during World War II when Nazi Germany researched and built operational ballistic missiles. Starting in the early 1930s, during the last stages of the Weimar Republic, German aerospace engineers experimented with liquid-fueled rockets...
A secretive army installation began in Kummersdorf-West in what year?
{ "text": [ "1932" ], "answer_start": [ 918 ] }
56e079e87aa994140058e541
Space_Race
During the Second World War, General Dornberger was the military head of the army's rocket program, Zanssen became the commandant of the Peenemünde army rocket centre, and von Braun was the technical director of the ballistic missile program. They would lead the team that built the Aggregate-4 (A-4) rocket, which becam...
During WWII, who was in charge of the German army's rocket program?
{ "text": [ "General Dornberger" ], "answer_start": [ 29 ] }
56e079e87aa994140058e542
Space_Race
During the Second World War, General Dornberger was the military head of the army's rocket program, Zanssen became the commandant of the Peenemünde army rocket centre, and von Braun was the technical director of the ballistic missile program. They would lead the team that built the Aggregate-4 (A-4) rocket, which becam...
What was the first object to enter space?
{ "text": [ "Aggregate-4 (A-4) rocket" ], "answer_start": [ 283 ] }
56e079e87aa994140058e543
Space_Race
During the Second World War, General Dornberger was the military head of the army's rocket program, Zanssen became the commandant of the Peenemünde army rocket centre, and von Braun was the technical director of the ballistic missile program. They would lead the team that built the Aggregate-4 (A-4) rocket, which becam...
When did the Aggregate-4 (A-4) rocket reach space?
{ "text": [ "1942 and 1943" ], "answer_start": [ 395 ] }
56e07a467aa994140058e549
Space_Race
At war's end, American, British, and Soviet scientific intelligence teams competed to capture Germany's rocket engineers along with the German rockets themselves and the designs on which they were based. Each of the Allies captured a share of the available members of the German rocket team, but the United States benefi...
What military operation allowed the US to recruit the German engineer, Von Braun?
{ "text": [ "Operation Paperclip" ], "answer_start": [ 338 ] }
56e07a467aa994140058e54a
Space_Race
At war's end, American, British, and Soviet scientific intelligence teams competed to capture Germany's rocket engineers along with the German rockets themselves and the designs on which they were based. Each of the Allies captured a share of the available members of the German rocket team, but the United States benefi...
The US had captured what type of missiles during Operation Paperclip?
{ "text": [ "V2 rockets" ], "answer_start": [ 551 ] }
56e07b187aa994140058e54d
Space_Race
The German rocket center in Peenemünde was located in the eastern part of Germany, which became the Soviet zone of occupation. On Stalin's orders, the Soviet Union sent its best rocket engineers to this region to see what they could salvage for future weapons systems. The Soviet rocket engineers were led by Sergei Koro...
The German rocket center was located in what city?
{ "text": [ "Peenemünde" ], "answer_start": [ 28 ] }
56e07b187aa994140058e54e
Space_Race
The German rocket center in Peenemünde was located in the eastern part of Germany, which became the Soviet zone of occupation. On Stalin's orders, the Soviet Union sent its best rocket engineers to this region to see what they could salvage for future weapons systems. The Soviet rocket engineers were led by Sergei Koro...
Who was in charge of the Soviet rocket engineer team that went into Germany?
{ "text": [ "Sergei Korolev" ], "answer_start": [ 309 ] }
56e07b187aa994140058e54f
Space_Race
The German rocket center in Peenemünde was located in the eastern part of Germany, which became the Soviet zone of occupation. On Stalin's orders, the Soviet Union sent its best rocket engineers to this region to see what they could salvage for future weapons systems. The Soviet rocket engineers were led by Sergei Koro...
What year was Sergei Korolev arrested?
{ "text": [ "1938" ], "answer_start": [ 426 ] }
56e07b187aa994140058e550
Space_Race
The German rocket center in Peenemünde was located in the eastern part of Germany, which became the Soviet zone of occupation. On Stalin's orders, the Soviet Union sent its best rocket engineers to this region to see what they could salvage for future weapons systems. The Soviet rocket engineers were led by Sergei Koro...
Sergei Korolev died in what year?
{ "text": [ "1966" ], "answer_start": [ 820 ] }
56e07b187aa994140058e551
Space_Race
The German rocket center in Peenemünde was located in the eastern part of Germany, which became the Soviet zone of occupation. On Stalin's orders, the Soviet Union sent its best rocket engineers to this region to see what they could salvage for future weapons systems. The Soviet rocket engineers were led by Sergei Koro...
After the war, Sergei Korolev was known under what title?
{ "text": [ "USSR's chief rocket and spacecraft engineer" ], "answer_start": [ 536 ] }
56e07b847aa994140058e559
Space_Race
After almost a year in the area around Peenemünde, Soviet officials moved most of the captured German rocket specialists to Gorodomlya Island on Lake Seliger, about 240 kilometers (150 mi) northwest of Moscow. They were not allowed to participate in Soviet missile design, but were used as problem-solving consultants to...
What year was the R1 rocket born?
{ "text": [ "1948" ], "answer_start": [ 792 ] }
56e07bc7231d4119001ac1c3
Space_Race
The American professor Robert H. Goddard had worked on developing solid-fuel rockets since 1914, and demonstrated a light battlefield rocket to the US Army Signal Corps only five days before the signing of the armistice that ended World War I. He also started developing liquid-fueled rockets in 1921; yet he had not bee...
What professor began working on solid-fuel rockets since 1914?
{ "text": [ "Robert H. Goddard" ], "answer_start": [ 23 ] }
56e07bc7231d4119001ac1c4
Space_Race
The American professor Robert H. Goddard had worked on developing solid-fuel rockets since 1914, and demonstrated a light battlefield rocket to the US Army Signal Corps only five days before the signing of the armistice that ended World War I. He also started developing liquid-fueled rockets in 1921; yet he had not bee...
Liquid-fueled rockets were developed in what year?
{ "text": [ "1921" ], "answer_start": [ 296 ] }
56e084b77aa994140058e595
Space_Race
Von Braun and his team were sent to the United States Army's White Sands Proving Ground, located in New Mexico, in 1945. They set about assembling the captured V2s and began a program of launching them and instructing American engineers in their operation. These tests led to the first rocket to take photos from outer s...
The United States Army's White Sands Proving Ground is located where?
{ "text": [ "New Mexico" ], "answer_start": [ 100 ] }
56e084b77aa994140058e596
Space_Race
Von Braun and his team were sent to the United States Army's White Sands Proving Ground, located in New Mexico, in 1945. They set about assembling the captured V2s and began a program of launching them and instructing American engineers in their operation. These tests led to the first rocket to take photos from outer s...
Von Braun and his associates were sent to United States Army's White Sands Proving Ground in what year?
{ "text": [ "1945" ], "answer_start": [ 115 ] }
56e084b77aa994140058e597
Space_Race
Von Braun and his team were sent to the United States Army's White Sands Proving Ground, located in New Mexico, in 1945. They set about assembling the captured V2s and began a program of launching them and instructing American engineers in their operation. These tests led to the first rocket to take photos from outer s...
The first two-stage rocket was developed in what year?
{ "text": [ "1949" ], "answer_start": [ 394 ] }
56e084b77aa994140058e598
Space_Race
Von Braun and his team were sent to the United States Army's White Sands Proving Ground, located in New Mexico, in 1945. They set about assembling the captured V2s and began a program of launching them and instructing American engineers in their operation. These tests led to the first rocket to take photos from outer s...
The Army's new Redstone Arsenal is located in what city and state?
{ "text": [ "Huntsville, Alabama" ], "answer_start": [ 496 ] }
56e084b77aa994140058e599
Space_Race
Von Braun and his team were sent to the United States Army's White Sands Proving Ground, located in New Mexico, in 1945. They set about assembling the captured V2s and began a program of launching them and instructing American engineers in their operation. These tests led to the first rocket to take photos from outer s...
What year was the German rocket team moved to Alabama?
{ "text": [ "1950" ], "answer_start": [ 520 ] }
56e08587231d4119001ac24f
Space_Race
In simple terms, the Cold War could be viewed as an expression of the ideological struggle between communism and capitalism. The United States faced a new uncertainty beginning in September 1949, when it lost its monopoly on the atomic bomb. American intelligence agencies discovered that the Soviet Union had exploded i...
What year did the US lose its monopoly to the atomic bomb?
{ "text": [ "1949" ], "answer_start": [ 190 ] }
56e08587231d4119001ac250
Space_Race
In simple terms, the Cold War could be viewed as an expression of the ideological struggle between communism and capitalism. The United States faced a new uncertainty beginning in September 1949, when it lost its monopoly on the atomic bomb. American intelligence agencies discovered that the Soviet Union had exploded i...
What type of bomb was first developed during the Cold War?
{ "text": [ "the hydrogen bomb" ], "answer_start": [ 605 ] }
56e08587231d4119001ac251
Space_Race
In simple terms, the Cold War could be viewed as an expression of the ideological struggle between communism and capitalism. The United States faced a new uncertainty beginning in September 1949, when it lost its monopoly on the atomic bomb. American intelligence agencies discovered that the Soviet Union had exploded i...
ICBMs is an abbreviation for what?
{ "text": [ "intercontinental strategic bombers and intercontinental ballistic missiles" ], "answer_start": [ 635 ] }
56e08587231d4119001ac252
Space_Race
In simple terms, the Cold War could be viewed as an expression of the ideological struggle between communism and capitalism. The United States faced a new uncertainty beginning in September 1949, when it lost its monopoly on the atomic bomb. American intelligence agencies discovered that the Soviet Union had exploded i...
The SAC is an abbreviation for what US force?
{ "text": [ "Strategic Air Command" ], "answer_start": [ 1220 ] }
56e08587231d4119001ac253
Space_Race
In simple terms, the Cold War could be viewed as an expression of the ideological struggle between communism and capitalism. The United States faced a new uncertainty beginning in September 1949, when it lost its monopoly on the atomic bomb. American intelligence agencies discovered that the Soviet Union had exploded i...
During what decade, did a fear of communism oversweep the US?
{ "text": [ "1950s" ], "answer_start": [ 837 ] }
56e08680231d4119001ac26b
Space_Race
For its part, the Soviet Union harbored fears of invasion. Having suffered at least 27 million casualties during World War II after being invaded by Nazi Germany in 1941, the Soviet Union was wary of its former ally, the United States, which until late 1949 was the sole possessor of atomic weapons. The United States ha...
How many casualties did the Soviet Union have during WWII?
{ "text": [ "27 million" ], "answer_start": [ 84 ] }
56e08680231d4119001ac26c
Space_Race
For its part, the Soviet Union harbored fears of invasion. Having suffered at least 27 million casualties during World War II after being invaded by Nazi Germany in 1941, the Soviet Union was wary of its former ally, the United States, which until late 1949 was the sole possessor of atomic weapons. The United States ha...
The Soviet Union was first invaded by Nazi controlled Germany in what year?
{ "text": [ "1941" ], "answer_start": [ 165 ] }
56e08680231d4119001ac26d
Space_Race
For its part, the Soviet Union harbored fears of invasion. Having suffered at least 27 million casualties during World War II after being invaded by Nazi Germany in 1941, the Soviet Union was wary of its former ally, the United States, which until late 1949 was the sole possessor of atomic weapons. The United States ha...
Until what year, was the US the sole possessor of the atomic bomb?
{ "text": [ "1949" ], "answer_start": [ 253 ] }