id stringlengths 24 24 | title stringlengths 3 59 | context stringlengths 151 3.71k | question stringlengths 12 217 | answers dict |
|---|---|---|---|---|
56e075f87aa994140058e509 | Aspirated_consonant | So-called voiced aspirated consonants are nearly always pronounced instead with breathy voice, a type of phonation or vibration of the vocal folds. The modifier letter ⟨◌ʰ⟩ after a voiced consonant actually represents a breathy-voiced or murmured dental stop, as with the "voiced aspirated" bilabial stop ⟨bʰ⟩ in the Ind... | What is breathy voice? | {
"text": [
"a type of phonation or vibration of the vocal folds"
],
"answer_start": [
95
]
} |
56e075f87aa994140058e50d | Aspirated_consonant | So-called voiced aspirated consonants are nearly always pronounced instead with breathy voice, a type of phonation or vibration of the vocal folds. The modifier letter ⟨◌ʰ⟩ after a voiced consonant actually represents a breathy-voiced or murmured dental stop, as with the "voiced aspirated" bilabial stop ⟨bʰ⟩ in the Ind... | The ⟨bʰ⟩ in the Indo-Aryan languages is better transcribed how for breathy voice? | {
"text": [
"⟨b̤⟩, with the diacritic"
],
"answer_start": [
398
]
} |
56e0769d7aa994140058e513 | Aspirated_consonant | Some linguists restrict the double-dot subscript ⟨◌̤⟩ to murmured sonorants, such as vowels and nasals, which are murmured throughout their duration, and use the superscript hook-aitch ⟨◌ʱ⟩ for the breathy-voiced release of obstruents. | What do some linguists restrict the double-dot subscript ⟨◌̤⟩ to? | {
"text": [
"murmured sonorants"
],
"answer_start": [
57
]
} |
56e0769d7aa994140058e514 | Aspirated_consonant | Some linguists restrict the double-dot subscript ⟨◌̤⟩ to murmured sonorants, such as vowels and nasals, which are murmured throughout their duration, and use the superscript hook-aitch ⟨◌ʱ⟩ for the breathy-voiced release of obstruents. | What are, according to the text, murmured for their duration? | {
"text": [
"vowels and nasals"
],
"answer_start": [
85
]
} |
56e0769d7aa994140058e515 | Aspirated_consonant | Some linguists restrict the double-dot subscript ⟨◌̤⟩ to murmured sonorants, such as vowels and nasals, which are murmured throughout their duration, and use the superscript hook-aitch ⟨◌ʱ⟩ for the breathy-voiced release of obstruents. | What uses the ⟨◌ʱ⟩? | {
"text": [
"breathy-voiced release of obstruents."
],
"answer_start": [
198
]
} |
56e0711b231d4119001ac141 | Hydrogen | Hydrogen is a chemical element with chemical symbol H and atomic number 1. With an atomic weight of 7000100794000000000♠1.00794 u, hydrogen is the lightest element on the periodic table. Its monatomic form (H) is the most abundant chemical substance in the Universe, constituting roughly 75% of all baryonic mass.[note 1... | What is hydrogens chemical symbol? | {
"text": [
"H"
],
"answer_start": [
0
]
} |
56e0711b231d4119001ac142 | Hydrogen | Hydrogen is a chemical element with chemical symbol H and atomic number 1. With an atomic weight of 7000100794000000000♠1.00794 u, hydrogen is the lightest element on the periodic table. Its monatomic form (H) is the most abundant chemical substance in the Universe, constituting roughly 75% of all baryonic mass.[note 1... | What is the atomic number used for hydrogen? | {
"text": [
"1"
],
"answer_start": [
72
]
} |
56e0711b231d4119001ac143 | Hydrogen | Hydrogen is a chemical element with chemical symbol H and atomic number 1. With an atomic weight of 7000100794000000000♠1.00794 u, hydrogen is the lightest element on the periodic table. Its monatomic form (H) is the most abundant chemical substance in the Universe, constituting roughly 75% of all baryonic mass.[note 1... | What is the atomic weight for hydrogen? | {
"text": [
"7000100794000000000♠1.00794 u"
],
"answer_start": [
100
]
} |
56e0711b231d4119001ac144 | Hydrogen | Hydrogen is a chemical element with chemical symbol H and atomic number 1. With an atomic weight of 7000100794000000000♠1.00794 u, hydrogen is the lightest element on the periodic table. Its monatomic form (H) is the most abundant chemical substance in the Universe, constituting roughly 75% of all baryonic mass.[note 1... | What element is considered the lightest? | {
"text": [
"Hydrogen"
],
"answer_start": [
0
]
} |
56e0733b231d4119001ac16d | Hydrogen | The universal emergence of atomic hydrogen first occurred during the recombination epoch. At standard temperature and pressure, hydrogen is a colorless, odorless, tasteless, non-toxic, nonmetallic, highly combustible diatomic gas with the molecular formula H2. Since hydrogen readily forms covalent compounds with most n... | What form can you find hydrogen is on Earth? | {
"text": [
"molecular"
],
"answer_start": [
239
]
} |
56e0733b231d4119001ac16e | Hydrogen | The universal emergence of atomic hydrogen first occurred during the recombination epoch. At standard temperature and pressure, hydrogen is a colorless, odorless, tasteless, non-toxic, nonmetallic, highly combustible diatomic gas with the molecular formula H2. Since hydrogen readily forms covalent compounds with most n... | What is the molecular make-up of hydrogen? | {
"text": [
"H2"
],
"answer_start": [
257
]
} |
56e0733b231d4119001ac16f | Hydrogen | The universal emergence of atomic hydrogen first occurred during the recombination epoch. At standard temperature and pressure, hydrogen is a colorless, odorless, tasteless, non-toxic, nonmetallic, highly combustible diatomic gas with the molecular formula H2. Since hydrogen readily forms covalent compounds with most n... | What are three properties of hydrogen at normal temperature and normal pressure? | {
"text": [
"colorless, odorless, tasteless"
],
"answer_start": [
142
]
} |
56e0733b231d4119001ac170 | Hydrogen | The universal emergence of atomic hydrogen first occurred during the recombination epoch. At standard temperature and pressure, hydrogen is a colorless, odorless, tasteless, non-toxic, nonmetallic, highly combustible diatomic gas with the molecular formula H2. Since hydrogen readily forms covalent compounds with most n... | What charge does hydrogen display in ionic compounds when it is called a hydride? | {
"text": [
"negative"
],
"answer_start": [
656
]
} |
56e0733b231d4119001ac171 | Hydrogen | The universal emergence of atomic hydrogen first occurred during the recombination epoch. At standard temperature and pressure, hydrogen is a colorless, odorless, tasteless, non-toxic, nonmetallic, highly combustible diatomic gas with the molecular formula H2. Since hydrogen readily forms covalent compounds with most n... | What field of study has hydrogen and it's properties played a key role in development? | {
"text": [
"quantum mechanics"
],
"answer_start": [
1159
]
} |
56e073a47aa994140058e4df | Hydrogen | Hydrogen gas was first artificially produced in the early 16th century, via the mixing of metals with acids. In 1766–81, Henry Cavendish was the first to recognize that hydrogen gas was a discrete substance, and that it produces water when burned, a property which later gave it its name: in Greek, hydrogen means "water... | When was hydrogen gas artificially produced for the first time? | {
"text": [
"early 16th century"
],
"answer_start": [
52
]
} |
56e073a47aa994140058e4e1 | Hydrogen | Hydrogen gas was first artificially produced in the early 16th century, via the mixing of metals with acids. In 1766–81, Henry Cavendish was the first to recognize that hydrogen gas was a discrete substance, and that it produces water when burned, a property which later gave it its name: in Greek, hydrogen means "water... | Who first recognized that hydrogen was a discrete substance? | {
"text": [
"Henry Cavendish"
],
"answer_start": [
121
]
} |
56e073a47aa994140058e4e2 | Hydrogen | Hydrogen gas was first artificially produced in the early 16th century, via the mixing of metals with acids. In 1766–81, Henry Cavendish was the first to recognize that hydrogen gas was a discrete substance, and that it produces water when burned, a property which later gave it its name: in Greek, hydrogen means "water... | When it is burned what does hydrogen make? | {
"text": [
"water"
],
"answer_start": [
229
]
} |
56e073a47aa994140058e4e3 | Hydrogen | Hydrogen gas was first artificially produced in the early 16th century, via the mixing of metals with acids. In 1766–81, Henry Cavendish was the first to recognize that hydrogen gas was a discrete substance, and that it produces water when burned, a property which later gave it its name: in Greek, hydrogen means "water... | What is the Greek translation for hydrogen? | {
"text": [
"water-former"
],
"answer_start": [
315
]
} |
56e074137aa994140058e4f5 | Hydrogen | Industrial production is mainly from the steam reforming of natural gas, and less often from more energy-intensive hydrogen production methods like the electrolysis of water. Most hydrogen is employed near its production site, with the two largest uses being fossil fuel processing (e.g., hydrocracking) and ammonia prod... | What market primarily uses ammonia production? | {
"text": [
"the fertilizer market"
],
"answer_start": [
339
]
} |
56e074137aa994140058e4f7 | Hydrogen | Industrial production is mainly from the steam reforming of natural gas, and less often from more energy-intensive hydrogen production methods like the electrolysis of water. Most hydrogen is employed near its production site, with the two largest uses being fossil fuel processing (e.g., hydrocracking) and ammonia prod... | Name a process that uses fossil fuels along with hydrogen. | {
"text": [
"hydrocracking"
],
"answer_start": [
289
]
} |
56e07476231d4119001ac17f | Hydrogen | Hydrogen gas (dihydrogen or molecular hydrogen) is highly flammable and will burn in air at a very wide range of concentrations between 4% and 75% by volume. The enthalpy of combustion for hydrogen is −286 kJ/mol: | For hydrogen what is the enthalpy of combustion? | {
"text": [
"286 kJ/mol"
],
"answer_start": [
202
]
} |
56e07476231d4119001ac180 | Hydrogen | Hydrogen gas (dihydrogen or molecular hydrogen) is highly flammable and will burn in air at a very wide range of concentrations between 4% and 75% by volume. The enthalpy of combustion for hydrogen is −286 kJ/mol: | What are two forms of hydrogen gas? | {
"text": [
"dihydrogen or molecular hydrogen"
],
"answer_start": [
14
]
} |
56e07476231d4119001ac181 | Hydrogen | Hydrogen gas (dihydrogen or molecular hydrogen) is highly flammable and will burn in air at a very wide range of concentrations between 4% and 75% by volume. The enthalpy of combustion for hydrogen is −286 kJ/mol: | Which element has a enthalpy of combustion at −286 kJ/mol? | {
"text": [
"Hydrogen"
],
"answer_start": [
0
]
} |
56e074de231d4119001ac18a | Hydrogen | Hydrogen gas forms explosive mixtures with air if it is 4–74% concentrated and with chlorine if it is 5–95% concentrated. The mixtures may be ignited by spark, heat or sunlight. The hydrogen autoignition temperature, the temperature of spontaneous ignition in air, is 500 °C (932 °F). Pure hydrogen-oxygen flames emit ul... | What kind of light do hydrogen-oxygen flames make? | {
"text": [
"ultraviolet light"
],
"answer_start": [
318
]
} |
56e074de231d4119001ac18b | Hydrogen | Hydrogen gas forms explosive mixtures with air if it is 4–74% concentrated and with chlorine if it is 5–95% concentrated. The mixtures may be ignited by spark, heat or sunlight. The hydrogen autoignition temperature, the temperature of spontaneous ignition in air, is 500 °C (932 °F). Pure hydrogen-oxygen flames emit ul... | What caused the Hindenburg to explode? | {
"text": [
"hydrogen combustion"
],
"answer_start": [
801
]
} |
56e0758e7aa994140058e503 | Hydrogen | H2 reacts with every oxidizing element. Hydrogen can react spontaneously and violently at room temperature with chlorine and fluorine to form the corresponding hydrogen halides, hydrogen chloride and hydrogen fluoride, which are also potentially dangerous acids. | What are two other dangerous acids? | {
"text": [
"hydrogen chloride and hydrogen fluoride"
],
"answer_start": [
178
]
} |
56e0758e7aa994140058e505 | Hydrogen | H2 reacts with every oxidizing element. Hydrogen can react spontaneously and violently at room temperature with chlorine and fluorine to form the corresponding hydrogen halides, hydrogen chloride and hydrogen fluoride, which are also potentially dangerous acids. | What temperature does hydrogen react with these elements? | {
"text": [
"room temperature"
],
"answer_start": [
90
]
} |
56e077207aa994140058e519 | Hydrogen | The energy levels of hydrogen can be calculated fairly accurately using the Bohr model of the atom, which conceptualizes the electron as "orbiting" the proton in analogy to the Earth's orbit of the Sun. However, the electromagnetic force attracts electrons and protons to one another, while planets and celestial objects... | What model id used to calculate energy levels of hydrogen? | {
"text": [
"Bohr model"
],
"answer_start": [
76
]
} |
56e077207aa994140058e51a | Hydrogen | The energy levels of hydrogen can be calculated fairly accurately using the Bohr model of the atom, which conceptualizes the electron as "orbiting" the proton in analogy to the Earth's orbit of the Sun. However, the electromagnetic force attracts electrons and protons to one another, while planets and celestial objects... | What attracts planets and celestial items? | {
"text": [
"gravity"
],
"answer_start": [
352
]
} |
56e077207aa994140058e51b | Hydrogen | The energy levels of hydrogen can be calculated fairly accurately using the Bohr model of the atom, which conceptualizes the electron as "orbiting" the proton in analogy to the Earth's orbit of the Sun. However, the electromagnetic force attracts electrons and protons to one another, while planets and celestial objects... | What does the electromagnetic force attract to one another? | {
"text": [
"electrons and protons"
],
"answer_start": [
247
]
} |
56e081487aa994140058e588 | Hydrogen | A more accurate description of the hydrogen atom comes from a purely quantum mechanical treatment that uses the Schrödinger equation, Dirac equation or even the Feynman path integral formulation to calculate the probability density of the electron around the proton. The most complicated treatments allow for the small e... | What kind of movement does the electron not have in ground state? | {
"text": [
"angular"
],
"answer_start": [
463
]
} |
56e087957aa994140058e5c1 | Hydrogen | There exist two different spin isomers of hydrogen diatomic molecules that differ by the relative spin of their nuclei. In the orthohydrogen form, the spins of the two protons are parallel and form a triplet state with a molecular spin quantum number of 1 (1⁄2+1⁄2); in the parahydrogen form the spins are antiparallel a... | How many different spin isomers exist? | {
"text": [
"2"
],
"answer_start": [
259
]
} |
56e087957aa994140058e5c2 | Hydrogen | There exist two different spin isomers of hydrogen diatomic molecules that differ by the relative spin of their nuclei. In the orthohydrogen form, the spins of the two protons are parallel and form a triplet state with a molecular spin quantum number of 1 (1⁄2+1⁄2); in the parahydrogen form the spins are antiparallel a... | What state are the protons in when in the orthohydrogen form? | {
"text": [
"triplet state"
],
"answer_start": [
200
]
} |
56e087957aa994140058e5c3 | Hydrogen | There exist two different spin isomers of hydrogen diatomic molecules that differ by the relative spin of their nuclei. In the orthohydrogen form, the spins of the two protons are parallel and form a triplet state with a molecular spin quantum number of 1 (1⁄2+1⁄2); in the parahydrogen form the spins are antiparallel a... | When hydrogen gas is in standard temperature and pressure, what form is it considered in> | {
"text": [
"normal"
],
"answer_start": [
524
]
} |
56e087957aa994140058e5c4 | Hydrogen | There exist two different spin isomers of hydrogen diatomic molecules that differ by the relative spin of their nuclei. In the orthohydrogen form, the spins of the two protons are parallel and form a triplet state with a molecular spin quantum number of 1 (1⁄2+1⁄2); in the parahydrogen form the spins are antiparallel a... | What percent of para form does hydrogen gas contain? | {
"text": [
"25%"
],
"answer_start": [
457
]
} |
56e087957aa994140058e5c5 | Hydrogen | There exist two different spin isomers of hydrogen diatomic molecules that differ by the relative spin of their nuclei. In the orthohydrogen form, the spins of the two protons are parallel and form a triplet state with a molecular spin quantum number of 1 (1⁄2+1⁄2); in the parahydrogen form the spins are antiparallel a... | What percent of ortho form does hydrogen gas contain? | {
"text": [
"75%"
],
"answer_start": [
482
]
} |
56e08a18231d4119001ac290 | Hydrogen | While H2 is not very reactive under standard conditions, it does form compounds with most elements. Hydrogen can form compounds with elements that are more electronegative, such as halogens (e.g., F, Cl, Br, I), or oxygen; in these compounds hydrogen takes on a partial positive charge. When bonded to fluorine, oxygen, ... | What ind of charge does hydrogen take when mixed with electronegative particles? | {
"text": [
"positive charge"
],
"answer_start": [
270
]
} |
56e08a18231d4119001ac291 | Hydrogen | While H2 is not very reactive under standard conditions, it does form compounds with most elements. Hydrogen can form compounds with elements that are more electronegative, such as halogens (e.g., F, Cl, Br, I), or oxygen; in these compounds hydrogen takes on a partial positive charge. When bonded to fluorine, oxygen, ... | What type of charge does hydrogen take when combined with a metal? | {
"text": [
"negative"
],
"answer_start": [
163
]
} |
56e08a18231d4119001ac292 | Hydrogen | While H2 is not very reactive under standard conditions, it does form compounds with most elements. Hydrogen can form compounds with elements that are more electronegative, such as halogens (e.g., F, Cl, Br, I), or oxygen; in these compounds hydrogen takes on a partial positive charge. When bonded to fluorine, oxygen, ... | When hydrogen forms with a metal, what is the compound called? | {
"text": [
"hydrides"
],
"answer_start": [
734
]
} |
56e08a18231d4119001ac293 | Hydrogen | While H2 is not very reactive under standard conditions, it does form compounds with most elements. Hydrogen can form compounds with elements that are more electronegative, such as halogens (e.g., F, Cl, Br, I), or oxygen; in these compounds hydrogen takes on a partial positive charge. When bonded to fluorine, oxygen, ... | Is H2 reactive in standard conditions? | {
"text": [
"not"
],
"answer_start": [
12
]
} |
56e08b457aa994140058e5e3 | Hydrogen | Hydrogen forms a vast array of compounds with carbon called the hydrocarbons, and an even vaster array with heteroatoms that, because of their general association with living things, are called organic compounds. The study of their properties is known as organic chemistry and their study in the context of living organi... | What is the form of hydrogen and carbon called? | {
"text": [
"hydrocarbons"
],
"answer_start": [
64
]
} |
56e08b457aa994140058e5e4 | Hydrogen | Hydrogen forms a vast array of compounds with carbon called the hydrocarbons, and an even vaster array with heteroatoms that, because of their general association with living things, are called organic compounds. The study of their properties is known as organic chemistry and their study in the context of living organi... | What is the form of hydrogen and heteroatoms called? | {
"text": [
"organic compounds"
],
"answer_start": [
194
]
} |
56e08b457aa994140058e5e5 | Hydrogen | Hydrogen forms a vast array of compounds with carbon called the hydrocarbons, and an even vaster array with heteroatoms that, because of their general association with living things, are called organic compounds. The study of their properties is known as organic chemistry and their study in the context of living organi... | What is the study of organic compounds properties known as? | {
"text": [
"organic chemistry"
],
"answer_start": [
255
]
} |
56e08b457aa994140058e5e6 | Hydrogen | Hydrogen forms a vast array of compounds with carbon called the hydrocarbons, and an even vaster array with heteroatoms that, because of their general association with living things, are called organic compounds. The study of their properties is known as organic chemistry and their study in the context of living organi... | What is the study of living organisms known as? | {
"text": [
"biochemistry"
],
"answer_start": [
336
]
} |
56e08b457aa994140058e5e7 | Hydrogen | Hydrogen forms a vast array of compounds with carbon called the hydrocarbons, and an even vaster array with heteroatoms that, because of their general association with living things, are called organic compounds. The study of their properties is known as organic chemistry and their study in the context of living organi... | Organic compounds are only required to conatin what? | {
"text": [
"carbon"
],
"answer_start": [
46
]
} |
56e090e27aa994140058e5ee | Hydrogen | Compounds of hydrogen are often called hydrides, a term that is used fairly loosely. The term "hydride" suggests that the H atom has acquired a negative or anionic character, denoted H−, and is used when hydrogen forms a compound with a more electropositive element. The existence of the hydride anion, suggested by Gilb... | Who suggested that hydride anions existed?character does the H atom have in a hydride? | {
"text": [
"Gilbert N. Lewis"
],
"answer_start": [
316
]
} |
56e090e27aa994140058e5f0 | Hydrogen | Compounds of hydrogen are often called hydrides, a term that is used fairly loosely. The term "hydride" suggests that the H atom has acquired a negative or anionic character, denoted H−, and is used when hydrogen forms a compound with a more electropositive element. The existence of the hydride anion, suggested by Gilb... | What group of hydrides is BEH considered polymeric? | {
"text": [
"group II"
],
"answer_start": [
672
]
} |
56e0914c7aa994140058e5f7 | Hydrogen | Although hydrides can be formed with almost all main-group elements, the number and combination of possible compounds varies widely; for example, there are over 100 binary borane hydrides known, but only one binary aluminium hydride. Binary indium hydride has not yet been identified, although larger complexes exist. | How many binary borane hydrides are known? | {
"text": [
"over 100"
],
"answer_start": [
156
]
} |
56e0914c7aa994140058e5f8 | Hydrogen | Although hydrides can be formed with almost all main-group elements, the number and combination of possible compounds varies widely; for example, there are over 100 binary borane hydrides known, but only one binary aluminium hydride. Binary indium hydride has not yet been identified, although larger complexes exist. | How many binary aluminum hydrides are there? | {
"text": [
"1"
],
"answer_start": [
161
]
} |
56e092177aa994140058e5fd | Hydrogen | In inorganic chemistry, hydrides can also serve as bridging ligands that link two metal centers in a coordination complex. This function is particularly common in group 13 elements, especially in boranes (boron hydrides) and aluminium complexes, as well as in clustered carboranes. | What chemistry do hydrides serve as bridging ligands? | {
"text": [
"inorganic chemistry"
],
"answer_start": [
3
]
} |
56e092177aa994140058e5fe | Hydrogen | In inorganic chemistry, hydrides can also serve as bridging ligands that link two metal centers in a coordination complex. This function is particularly common in group 13 elements, especially in boranes (boron hydrides) and aluminium complexes, as well as in clustered carboranes. | What do hydrides that are bridging ligands link up? | {
"text": [
"link two metal centers"
],
"answer_start": [
73
]
} |
56e092177aa994140058e5ff | Hydrogen | In inorganic chemistry, hydrides can also serve as bridging ligands that link two metal centers in a coordination complex. This function is particularly common in group 13 elements, especially in boranes (boron hydrides) and aluminium complexes, as well as in clustered carboranes. | What group is briging ligands most common in? | {
"text": [
"group 13"
],
"answer_start": [
163
]
} |
56e09c507aa994140058e64d | Hydrogen | Oxidation of hydrogen removes its electron and gives H+, which contains no electrons and a nucleus which is usually composed of one proton. That is why H+ is often called a proton. This species is central to discussion of acids. Under the Bronsted-Lowry theory, acids are proton donors, while bases are proton acceptors. | When hydrogen oxidates, what is it removing? | {
"text": [
"electrons"
],
"answer_start": [
75
]
} |
56e09c507aa994140058e64e | Hydrogen | Oxidation of hydrogen removes its electron and gives H+, which contains no electrons and a nucleus which is usually composed of one proton. That is why H+ is often called a proton. This species is central to discussion of acids. Under the Bronsted-Lowry theory, acids are proton donors, while bases are proton acceptors. | When hydrogen oxidates, what does it end up giving? | {
"text": [
"H+"
],
"answer_start": [
53
]
} |
56e09c507aa994140058e651 | Hydrogen | Oxidation of hydrogen removes its electron and gives H+, which contains no electrons and a nucleus which is usually composed of one proton. That is why H+ is often called a proton. This species is central to discussion of acids. Under the Bronsted-Lowry theory, acids are proton donors, while bases are proton acceptors. | What theory suggests that acids are proton donors? | {
"text": [
"Bronsted-Lowry"
],
"answer_start": [
239
]
} |
56e09d01231d4119001ac2d3 | Hydrogen | A bare proton, H+, cannot exist in solution or in ionic crystals, because of its unstoppable attraction to other atoms or molecules with electrons. Except at the high temperatures associated with plasmas, such protons cannot be removed from the electron clouds of atoms and molecules, and will remain attached to them. H... | What is another term for a bare proton? | {
"text": [
"H+"
],
"answer_start": [
15
]
} |
56e0af0c231d4119001ac34d | Hydrogen | To avoid the implication of the naked "solvated proton" in solution, acidic aqueous solutions are sometimes considered to contain a less unlikely fictitious species, termed the "hydronium ion" (H 3O+). However, even in this case, such solvated hydrogen cations are more realistically conceived as being organized into cl... | Where can oxonium ions be found? | {
"text": [
"in acidic solution with other solvents"
],
"answer_start": [
407
]
} |
56e0af0c231d4119001ac34e | Hydrogen | To avoid the implication of the naked "solvated proton" in solution, acidic aqueous solutions are sometimes considered to contain a less unlikely fictitious species, termed the "hydronium ion" (H 3O+). However, even in this case, such solvated hydrogen cations are more realistically conceived as being organized into cl... | What other term is a solvated protons referred as? | {
"text": [
"hydronium ion"
],
"answer_start": [
178
]
} |
56e0afa2231d4119001ac354 | Hydrogen | Although exotic on Earth, one of the most common ions in the universe is the H+ 3 ion, known as protonated molecular hydrogen or the trihydrogen cation. | What kind of molecular hydrogen is the H+3 knows as? | {
"text": [
"protonated"
],
"answer_start": [
96
]
} |
56e0afa2231d4119001ac355 | Hydrogen | Although exotic on Earth, one of the most common ions in the universe is the H+ 3 ion, known as protonated molecular hydrogen or the trihydrogen cation. | What kind of cation is the H+3 knowns as? | {
"text": [
"trihydrogen cation"
],
"answer_start": [
133
]
} |
56e0b0667aa994140058e6a5 | Hydrogen | Hydrogen has three naturally occurring isotopes, denoted 1H, 2H and 3H. Other, highly unstable nuclei (4H to 7H) have been synthesized in the laboratory but not observed in nature. | How many natural isotopes does hydrogen have> | {
"text": [
"3H"
],
"answer_start": [
68
]
} |
56e0b0667aa994140058e6a6 | Hydrogen | Hydrogen has three naturally occurring isotopes, denoted 1H, 2H and 3H. Other, highly unstable nuclei (4H to 7H) have been synthesized in the laboratory but not observed in nature. | What are the names of these isotopes? | {
"text": [
"denoted 1H, 2H and 3H"
],
"answer_start": [
49
]
} |
56e0b0667aa994140058e6a7 | Hydrogen | Hydrogen has three naturally occurring isotopes, denoted 1H, 2H and 3H. Other, highly unstable nuclei (4H to 7H) have been synthesized in the laboratory but not observed in nature. | Which isotopes have unstable nuclei? | {
"text": [
"4H to 7H"
],
"answer_start": [
103
]
} |
56e0b2127aa994140058e6ad | Hydrogen | Hydrogen is the only element that has different names for its isotopes in common use today. During the early study of radioactivity, various heavy radioactive isotopes were given their own names, but such names are no longer used, except for deuterium and tritium. The symbols D and T (instead of 2H and 3H) are sometime... | Which element is the only that has different names for its isotopes? | {
"text": [
"Hydrogen"
],
"answer_start": [
0
]
} |
56e0b2127aa994140058e6ae | Hydrogen | Hydrogen is the only element that has different names for its isotopes in common use today. During the early study of radioactivity, various heavy radioactive isotopes were given their own names, but such names are no longer used, except for deuterium and tritium. The symbols D and T (instead of 2H and 3H) are sometime... | What are the only two names still used for radioactive isotopes? | {
"text": [
"deuterium and tritium"
],
"answer_start": [
242
]
} |
56e0b2127aa994140058e6af | Hydrogen | Hydrogen is the only element that has different names for its isotopes in common use today. During the early study of radioactivity, various heavy radioactive isotopes were given their own names, but such names are no longer used, except for deuterium and tritium. The symbols D and T (instead of 2H and 3H) are sometime... | What are the symbols used for deuterium and tritium? | {
"text": [
"D and T"
],
"answer_start": [
277
]
} |
56e0b2127aa994140058e6b0 | Hydrogen | Hydrogen is the only element that has different names for its isotopes in common use today. During the early study of radioactivity, various heavy radioactive isotopes were given their own names, but such names are no longer used, except for deuterium and tritium. The symbols D and T (instead of 2H and 3H) are sometime... | What does the symbol P represent? | {
"text": [
"phosphorus"
],
"answer_start": [
421
]
} |
56e0b2127aa994140058e6b1 | Hydrogen | Hydrogen is the only element that has different names for its isotopes in common use today. During the early study of radioactivity, various heavy radioactive isotopes were given their own names, but such names are no longer used, except for deuterium and tritium. The symbols D and T (instead of 2H and 3H) are sometime... | What are the preferred symbols for deuterium and tritium? | {
"text": [
"2H and 3H"
],
"answer_start": [
297
]
} |
56e16a26e3433e1400422ed6 | Hydrogen | In 1671, Robert Boyle discovered and described the reaction between iron filings and dilute acids, which results in the production of hydrogen gas. In 1766, Henry Cavendish was the first to recognize hydrogen gas as a discrete substance, by naming the gas from a metal-acid reaction "flammable air". He speculated that "... | What year was the discovery of hydrogen gas? | {
"text": [
"1671"
],
"answer_start": [
3
]
} |
56e16a26e3433e1400422ed7 | Hydrogen | In 1671, Robert Boyle discovered and described the reaction between iron filings and dilute acids, which results in the production of hydrogen gas. In 1766, Henry Cavendish was the first to recognize hydrogen gas as a discrete substance, by naming the gas from a metal-acid reaction "flammable air". He speculated that "... | Who discovered Hydrogen gas? | {
"text": [
"Robert Boyle"
],
"answer_start": [
9
]
} |
56e16a26e3433e1400422ed8 | Hydrogen | In 1671, Robert Boyle discovered and described the reaction between iron filings and dilute acids, which results in the production of hydrogen gas. In 1766, Henry Cavendish was the first to recognize hydrogen gas as a discrete substance, by naming the gas from a metal-acid reaction "flammable air". He speculated that "... | Who recognized hydrogen gas as a discreet substance? | {
"text": [
"Henry Cavendish"
],
"answer_start": [
157
]
} |
56e16a26e3433e1400422ed9 | Hydrogen | In 1671, Robert Boyle discovered and described the reaction between iron filings and dilute acids, which results in the production of hydrogen gas. In 1766, Henry Cavendish was the first to recognize hydrogen gas as a discrete substance, by naming the gas from a metal-acid reaction "flammable air". He speculated that "... | In what year did Henry Cavendish recognize hydrogen gas as a discreet substance? | {
"text": [
"1766"
],
"answer_start": [
151
]
} |
56e16a26e3433e1400422eda | Hydrogen | In 1671, Robert Boyle discovered and described the reaction between iron filings and dilute acids, which results in the production of hydrogen gas. In 1766, Henry Cavendish was the first to recognize hydrogen gas as a discrete substance, by naming the gas from a metal-acid reaction "flammable air". He speculated that "... | What does gas produce when burned? | {
"text": [
"water"
],
"answer_start": [
457
]
} |
56e16b59cd28a01900c678dd | Hydrogen | Hydrogen was liquefied for the first time by James Dewar in 1898 by using regenerative cooling and his invention, the vacuum flask. He produced solid hydrogen the next year. Deuterium was discovered in December 1931 by Harold Urey, and tritium was prepared in 1934 by Ernest Rutherford, Mark Oliphant, and Paul Harteck. ... | Who was the first to liquidize hydrogen? | {
"text": [
"James Dewar"
],
"answer_start": [
45
]
} |
56e16b59cd28a01900c678de | Hydrogen | Hydrogen was liquefied for the first time by James Dewar in 1898 by using regenerative cooling and his invention, the vacuum flask. He produced solid hydrogen the next year. Deuterium was discovered in December 1931 by Harold Urey, and tritium was prepared in 1934 by Ernest Rutherford, Mark Oliphant, and Paul Harteck. ... | In what year Did James Dewar first liquidize hydrogen? | {
"text": [
"1898"
],
"answer_start": [
60
]
} |
56e16b59cd28a01900c678df | Hydrogen | Hydrogen was liquefied for the first time by James Dewar in 1898 by using regenerative cooling and his invention, the vacuum flask. He produced solid hydrogen the next year. Deuterium was discovered in December 1931 by Harold Urey, and tritium was prepared in 1934 by Ernest Rutherford, Mark Oliphant, and Paul Harteck. ... | What year was Deuterium discovered? | {
"text": [
"1931"
],
"answer_start": [
211
]
} |
56e16b59cd28a01900c678e0 | Hydrogen | Hydrogen was liquefied for the first time by James Dewar in 1898 by using regenerative cooling and his invention, the vacuum flask. He produced solid hydrogen the next year. Deuterium was discovered in December 1931 by Harold Urey, and tritium was prepared in 1934 by Ernest Rutherford, Mark Oliphant, and Paul Harteck. ... | Who was the first to discover deuterium? | {
"text": [
"Harold Urey"
],
"answer_start": [
219
]
} |
56e16b59cd28a01900c678e1 | Hydrogen | Hydrogen was liquefied for the first time by James Dewar in 1898 by using regenerative cooling and his invention, the vacuum flask. He produced solid hydrogen the next year. Deuterium was discovered in December 1931 by Harold Urey, and tritium was prepared in 1934 by Ernest Rutherford, Mark Oliphant, and Paul Harteck. ... | What year was tritium discovered? | {
"text": [
"1934"
],
"answer_start": [
260
]
} |
56e16c1ae3433e1400422efa | Hydrogen | The first hydrogen-filled balloon was invented by Jacques Charles in 1783. Hydrogen provided the lift for the first reliable form of air-travel following the 1852 invention of the first hydrogen-lifted airship by Henri Giffard. German count Ferdinand von Zeppelin promoted the idea of rigid airships lifted by hydrogen t... | Who invented the hydrogen filled balloons? | {
"text": [
"Jacques Charles"
],
"answer_start": [
50
]
} |
56e16c1ae3433e1400422efb | Hydrogen | The first hydrogen-filled balloon was invented by Jacques Charles in 1783. Hydrogen provided the lift for the first reliable form of air-travel following the 1852 invention of the first hydrogen-lifted airship by Henri Giffard. German count Ferdinand von Zeppelin promoted the idea of rigid airships lifted by hydrogen t... | What year was hydrogen filled balloons invented? | {
"text": [
"1783"
],
"answer_start": [
69
]
} |
56e16c1ae3433e1400422efd | Hydrogen | The first hydrogen-filled balloon was invented by Jacques Charles in 1783. Hydrogen provided the lift for the first reliable form of air-travel following the 1852 invention of the first hydrogen-lifted airship by Henri Giffard. German count Ferdinand von Zeppelin promoted the idea of rigid airships lifted by hydrogen t... | what were the hydrogen lifted airships called? | {
"text": [
"Zeppelins"
],
"answer_start": [
342
]
} |
56e16c1ae3433e1400422efe | Hydrogen | The first hydrogen-filled balloon was invented by Jacques Charles in 1783. Hydrogen provided the lift for the first reliable form of air-travel following the 1852 invention of the first hydrogen-lifted airship by Henri Giffard. German count Ferdinand von Zeppelin promoted the idea of rigid airships lifted by hydrogen t... | In what year did the first zeppelin make flight? | {
"text": [
"1900"
],
"answer_start": [
397
]
} |
56e16ce5cd28a01900c67907 | Hydrogen | The first non-stop transatlantic crossing was made by the British airship R34 in 1919. Regular passenger service resumed in the 1920s and the discovery of helium reserves in the United States promised increased safety, but the U.S. government refused to sell the gas for this purpose. Therefore, H2 was used in the Hinde... | Who made the first non stop transatlantic crossing? | {
"text": [
"the British"
],
"answer_start": [
54
]
} |
56e16ce5cd28a01900c67908 | Hydrogen | The first non-stop transatlantic crossing was made by the British airship R34 in 1919. Regular passenger service resumed in the 1920s and the discovery of helium reserves in the United States promised increased safety, but the U.S. government refused to sell the gas for this purpose. Therefore, H2 was used in the Hinde... | What year was this done? | {
"text": [
"1919"
],
"answer_start": [
81
]
} |
56e16ce5cd28a01900c6790a | Hydrogen | The first non-stop transatlantic crossing was made by the British airship R34 in 1919. Regular passenger service resumed in the 1920s and the discovery of helium reserves in the United States promised increased safety, but the U.S. government refused to sell the gas for this purpose. Therefore, H2 was used in the Hinde... | What year did the airship get destroyed? | {
"text": [
"1937"
],
"answer_start": [
397
]
} |
56e16ce5cd28a01900c6790b | Hydrogen | The first non-stop transatlantic crossing was made by the British airship R34 in 1919. Regular passenger service resumed in the 1920s and the discovery of helium reserves in the United States promised increased safety, but the U.S. government refused to sell the gas for this purpose. Therefore, H2 was used in the Hinde... | What city was the ship over when it caught fire? | {
"text": [
"New Jersey"
],
"answer_start": [
377
]
} |
56e170cfcd28a01900c67937 | Hydrogen | In the same year the first hydrogen-cooled turbogenerator went into service with gaseous hydrogen as a coolant in the rotor and the stator in 1937 at Dayton, Ohio, by the Dayton Power & Light Co.; because of the thermal conductivity of hydrogen gas, this is the most common type in its field today. | In what year did the first hydrogen cooled turbogenerator go into service? | {
"text": [
"1937"
],
"answer_start": [
142
]
} |
56e170cfcd28a01900c67939 | Hydrogen | In the same year the first hydrogen-cooled turbogenerator went into service with gaseous hydrogen as a coolant in the rotor and the stator in 1937 at Dayton, Ohio, by the Dayton Power & Light Co.; because of the thermal conductivity of hydrogen gas, this is the most common type in its field today. | What state is the Dayton Power and light Company located? | {
"text": [
"Ohio"
],
"answer_start": [
158
]
} |
56e176a2cd28a01900c6797b | Hydrogen | The nickel hydrogen battery was used for the first time in 1977 aboard the U.S. Navy's Navigation technology satellite-2 (NTS-2). For example, the ISS, Mars Odyssey and the Mars Global Surveyor are equipped with nickel-hydrogen batteries. In the dark part of its orbit, the Hubble Space Telescope is also powered by nick... | What year was the first nickel hydrogen battery used? | {
"text": [
"1977"
],
"answer_start": [
59
]
} |
56e176a2cd28a01900c6797e | Hydrogen | The nickel hydrogen battery was used for the first time in 1977 aboard the U.S. Navy's Navigation technology satellite-2 (NTS-2). For example, the ISS, Mars Odyssey and the Mars Global Surveyor are equipped with nickel-hydrogen batteries. In the dark part of its orbit, the Hubble Space Telescope is also powered by nick... | In what year did the hubble space telescope finally get the nickel hydrogen battery? | {
"text": [
"2009"
],
"answer_start": [
378
]
} |
56e17de1e3433e1400422f78 | Hydrogen | Because of its simple atomic structure, consisting only of a proton and an electron, the hydrogen atom, together with the spectrum of light produced from it or absorbed by it, has been central to the development of the theory of atomic structure. Furthermore, the corresponding simplicity of the hydrogen molecule and th... | What is the hydrogen atom made up of? | {
"text": [
"a proton and an electron"
],
"answer_start": [
59
]
} |
56e17de1e3433e1400422f79 | Hydrogen | Because of its simple atomic structure, consisting only of a proton and an electron, the hydrogen atom, together with the spectrum of light produced from it or absorbed by it, has been central to the development of the theory of atomic structure. Furthermore, the corresponding simplicity of the hydrogen molecule and th... | What theory is the hydrogen atom a big part of? | {
"text": [
"atomic structure"
],
"answer_start": [
22
]
} |
56e17de1e3433e1400422f7a | Hydrogen | Because of its simple atomic structure, consisting only of a proton and an electron, the hydrogen atom, together with the spectrum of light produced from it or absorbed by it, has been central to the development of the theory of atomic structure. Furthermore, the corresponding simplicity of the hydrogen molecule and th... | When was the quantum mechanical treatment of the hydrogen atom developed? | {
"text": [
"1920s"
],
"answer_start": [
526
]
} |
56e17f00e3433e1400422f86 | Hydrogen | One of the first quantum effects to be explicitly noticed (but not understood at the time) was a Maxwell observation involving hydrogen, half a century before full quantum mechanical theory arrived. Maxwell observed that the specific heat capacity of H2 unaccountably departs from that of a diatomic gas below room tempe... | Who observed the specific heat capacity of H2? | {
"text": [
"Maxwell"
],
"answer_start": [
97
]
} |
56e17f00e3433e1400422f87 | Hydrogen | One of the first quantum effects to be explicitly noticed (but not understood at the time) was a Maxwell observation involving hydrogen, half a century before full quantum mechanical theory arrived. Maxwell observed that the specific heat capacity of H2 unaccountably departs from that of a diatomic gas below room tempe... | What cause H2 to resemble monatomic gas? | {
"text": [
"spacing of the (quantized) rotational energy levels"
],
"answer_start": [
473
]
} |
56e17f00e3433e1400422f88 | Hydrogen | One of the first quantum effects to be explicitly noticed (but not understood at the time) was a Maxwell observation involving hydrogen, half a century before full quantum mechanical theory arrived. Maxwell observed that the specific heat capacity of H2 unaccountably departs from that of a diatomic gas below room tempe... | What theory supports this? | {
"text": [
"quantum theory"
],
"answer_start": [
427
]
} |
56e1934be3433e1400422fd2 | Hydrogen | Hydrogen, as atomic H, is the most abundant chemical element in the universe, making up 75% of normal matter by mass and over 90% by number of atoms (most of the mass of the universe, however, is not in the form of chemical-element type matter, but rather is postulated to occur as yet-undetected forms of mass such as d... | What percent of normal matter is hydrogen? | {
"text": [
"75%"
],
"answer_start": [
88
]
} |
56e1934be3433e1400422fd3 | Hydrogen | Hydrogen, as atomic H, is the most abundant chemical element in the universe, making up 75% of normal matter by mass and over 90% by number of atoms (most of the mass of the universe, however, is not in the form of chemical-element type matter, but rather is postulated to occur as yet-undetected forms of mass such as d... | What percent of atoms is hydrogen? | {
"text": [
"90%"
],
"answer_start": [
126
]
} |
56e1934be3433e1400422fd4 | Hydrogen | Hydrogen, as atomic H, is the most abundant chemical element in the universe, making up 75% of normal matter by mass and over 90% by number of atoms (most of the mass of the universe, however, is not in the form of chemical-element type matter, but rather is postulated to occur as yet-undetected forms of mass such as d... | What 2 forms of mass is most of the universe consisted of? | {
"text": [
"dark matter and dark energy"
],
"answer_start": [
319
]
} |
56e1934be3433e1400422fd6 | Hydrogen | Hydrogen, as atomic H, is the most abundant chemical element in the universe, making up 75% of normal matter by mass and over 90% by number of atoms (most of the mass of the universe, however, is not in the form of chemical-element type matter, but rather is postulated to occur as yet-undetected forms of mass such as d... | Clouds of H2 form what? | {
"text": [
"stars"
],
"answer_start": [
393
]
} |
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