id
stringlengths
24
24
question
stringlengths
1
270
answer
stringlengths
1
239
documents
listlengths
1
1
56e06851231d4119001ac0b5
The Sami tongue also has what?
Preaspirated stops
[ "Aspirated_consonant\n\nPreaspirated stops also occur in most Sami languages; for example, in North Sami, the unvoiced stop and affricate phonemes /p/, /t/, /ts/, /tʃ/, /k/ are pronounced preaspirated ([ʰp], [ʰt] [ʰts], [ʰtʃ], [ʰk]) when they occur in medial or final position." ]
56e06851231d4119001ac0b6
Which Sami tongue has unvoiced stop and affricate phonemes pronounced preaspirated?
North Sami
[ "Aspirated_consonant\n\nPreaspirated stops also occur in most Sami languages; for example, in North Sami, the unvoiced stop and affricate phonemes /p/, /t/, /ts/, /tʃ/, /k/ are pronounced preaspirated ([ʰp], [ʰt] [ʰts], [ʰtʃ], [ʰk]) when they occur in medial or final position." ]
56e06908231d4119001ac0c4
How many contrastive aspirated fricatives does Choni Tibetan have?
up to four
[ "Aspirated_consonant\n\nAlthough most aspirated obstruents in the world's language are stops and affricates, aspirated fricatives such as [sʰ], [fʰ] or [ɕʰ] have been documented in Korean, in a few Tibeto-Burman languages, in some Oto-Manguean languages, and in the Siouan language Ofo. Some languages, such as Choni...
56e069f0231d4119001ac0d1
Indian languages commonly have murmured consonants instead of what?
True aspirated voiced consonants
[ "Aspirated_consonant\n\nTrue aspirated voiced consonants, as opposed to murmured (breathy-voice) consonants such as the [bʱ], [dʱ], [ɡʱ] that are common in the languages of India, are extremely rare. They have been documented in Kelabit Taa, and the Kx'a languages. Reported aspirated voiced stops, affricates and cl...
56e069f0231d4119001ac0d2
True aspirated consonants are considered what?
rare
[ "Aspirated_consonant\n\nTrue aspirated voiced consonants, as opposed to murmured (breathy-voice) consonants such as the [bʱ], [dʱ], [ɡʱ] that are common in the languages of India, are extremely rare. They have been documented in Kelabit Taa, and the Kx'a languages. Reported aspirated voiced stops, affricates and cl...
56e069f0231d4119001ac0d3
True aspirated consonants have been found in Kelabit Taa and what else?
Kx'a languages
[ "Aspirated_consonant\n\nTrue aspirated voiced consonants, as opposed to murmured (breathy-voice) consonants such as the [bʱ], [dʱ], [ɡʱ] that are common in the languages of India, are extremely rare. They have been documented in Kelabit Taa, and the Kx'a languages. Reported aspirated voiced stops, affricates and cl...
56e06a517aa994140058e479
What has a different significance in various languages?
Aspiration
[ "Aspirated_consonant\n\nAspiration has varying significance in different languages. It is either allophonic or phonemic, and may be analyzed as an underlying consonant cluster." ]
56e06a517aa994140058e47a
What two forms can aspiration be in?
allophonic or phonemic
[ "Aspirated_consonant\n\nAspiration has varying significance in different languages. It is either allophonic or phonemic, and may be analyzed as an underlying consonant cluster." ]
56e06ab2231d4119001ac0dd
Aspiration is what, in English and some other languages?
allophonic
[ "Aspirated_consonant\n\nIn some languages, such as English, aspiration is allophonic. Stops are distinguished primarily by voicing, and voiceless stops are sometimes aspirated, while voiced stops are usually unaspirated." ]
56e06ab2231d4119001ac0de
How are stops distinguished?
voicing
[ "Aspirated_consonant\n\nIn some languages, such as English, aspiration is allophonic. Stops are distinguished primarily by voicing, and voiceless stops are sometimes aspirated, while voiced stops are usually unaspirated." ]
56e06ab2231d4119001ac0df
Voiceless stops are at times what?
aspirated
[ "Aspirated_consonant\n\nIn some languages, such as English, aspiration is allophonic. Stops are distinguished primarily by voicing, and voiceless stops are sometimes aspirated, while voiced stops are usually unaspirated." ]
56e06ab2231d4119001ac0e0
Voiced stops are most often what?
unaspirated
[ "Aspirated_consonant\n\nIn some languages, such as English, aspiration is allophonic. Stops are distinguished primarily by voicing, and voiceless stops are sometimes aspirated, while voiced stops are usually unaspirated." ]
56e06b78231d4119001ac0e5
When following a word such as spill, they are what for most speakers?
unaspirated
[ "Aspirated_consonant\n\nThey are unaspirated for almost all speakers when immediately following word-initial s, as in spill, still, skill. After an s elsewhere in a word they are normally unaspirated as well, except sometimes in compound words. When the consonants in a cluster like st are analyzed as belonging to d...
56e06b78231d4119001ac0e6
If the letter s is a different place in the word, it is typical unaspirated unless the word is what?
compound words
[ "Aspirated_consonant\n\nThey are unaspirated for almost all speakers when immediately following word-initial s, as in spill, still, skill. After an s elsewhere in a word they are normally unaspirated as well, except sometimes in compound words. When the consonants in a cluster like st are analyzed as belonging to d...
56e06b78231d4119001ac0e7
If there is a cluster such as st and it belongs to different morphemes, the stop is what?
aspirated
[ "Aspirated_consonant\n\nThey are unaspirated for almost all speakers when immediately following word-initial s, as in spill, still, skill. After an s elsewhere in a word they are normally unaspirated as well, except sometimes in compound words. When the consonants in a cluster like st are analyzed as belonging to d...
56e06b78231d4119001ac0e8
If the st belongs to one morpheme, then the stop is what?
unaspirated
[ "Aspirated_consonant\n\nThey are unaspirated for almost all speakers when immediately following word-initial s, as in spill, still, skill. After an s elsewhere in a word they are normally unaspirated as well, except sometimes in compound words. When the consonants in a cluster like st are analyzed as belonging to d...
56e06bd2231d4119001ac0ed
In languages like Thai and Icelandic, tenuis and aspirated consonants are what?
phonemic
[ "Aspirated_consonant\n\nIn many languages, such as Armenian, Korean, Thai, Indo-Aryan languages, Dravidian languages, Icelandic, Ancient Greek, and the varieties of Chinese, tenuis and aspirated consonants are phonemic. Unaspirated consonants like [p˭ s˭] and aspirated consonants like [pʰ ʰp sʰ] are separate phonem...
56e06bd2231d4119001ac0ee
[p˭ s˭] and [pʰ ʰp sʰ] are separate what?
phonemes
[ "Aspirated_consonant\n\nIn many languages, such as Armenian, Korean, Thai, Indo-Aryan languages, Dravidian languages, Icelandic, Ancient Greek, and the varieties of Chinese, tenuis and aspirated consonants are phonemic. Unaspirated consonants like [p˭ s˭] and aspirated consonants like [pʰ ʰp sʰ] are separate phonem...
56e06c697aa994140058e493
How are lenis consonants distinguished from fortis consonants?
their lack of aspiration
[ "Aspirated_consonant\n\nIn Danish and most southern varieties of German, the \"lenis\" consonants transcribed for historical reasons as ⟨b d ɡ⟩ are distinguished from their fortis counterparts ⟨p t k⟩, mainly in their lack of aspiration." ]
56e06c697aa994140058e494
If the lenis are ⟨b d ɡ⟩, what are the fortis counterparts?
⟨p t k⟩
[ "Aspirated_consonant\n\nIn Danish and most southern varieties of German, the \"lenis\" consonants transcribed for historical reasons as ⟨b d ɡ⟩ are distinguished from their fortis counterparts ⟨p t k⟩, mainly in their lack of aspiration." ]
56e06cd3231d4119001ac0fd
Mandarin has stops and affricates that are distinguished by what?
aspiration
[ "Aspirated_consonant\n\nStandard Chinese (Mandarin) has stops and affricates distinguished by aspiration: for instance, /t tʰ/, /t͡s t͡sʰ/. In pinyin, tenuis stops are written with letters that represent voiced consonants in English, and aspirated stops with letters that represent voiceless consonants. Thus d repre...
56e06cd3231d4119001ac0fe
Tenuis stops have letters that are representative of English voiced consonant in what?
pinyin
[ "Aspirated_consonant\n\nStandard Chinese (Mandarin) has stops and affricates distinguished by aspiration: for instance, /t tʰ/, /t͡s t͡sʰ/. In pinyin, tenuis stops are written with letters that represent voiced consonants in English, and aspirated stops with letters that represent voiceless consonants. Thus d repre...
56e06cd3231d4119001ac0ff
What kind of stops in pinyin are written with letters that representative of voiceless consonants?
aspirated stops
[ "Aspirated_consonant\n\nStandard Chinese (Mandarin) has stops and affricates distinguished by aspiration: for instance, /t tʰ/, /t͡s t͡sʰ/. In pinyin, tenuis stops are written with letters that represent voiced consonants in English, and aspirated stops with letters that represent voiceless consonants. Thus d repre...
56e06d44231d4119001ac103
What has a three-way distinction in regards to stops and affricates?
Wu Chinese
[ "Aspirated_consonant\n\nWu Chinese has a three-way distinction in stops and affricates: /p pʰ b/. In addition to aspirated and unaspirated consonants, there is a series of muddy consonants, like /b/. These are pronounced with slack or breathy voice: that is, they are weakly voiced. Muddy consonants as initial cause...
56e06d44231d4119001ac104
What is the actual distinction for Wu Chinese?
/p pʰ b/
[ "Aspirated_consonant\n\nWu Chinese has a three-way distinction in stops and affricates: /p pʰ b/. In addition to aspirated and unaspirated consonants, there is a series of muddy consonants, like /b/. These are pronounced with slack or breathy voice: that is, they are weakly voiced. Muddy consonants as initial cause...
56e06d44231d4119001ac105
What is /b/ representative of, in addition to aspirated and unaspirated consonants?
Muddy consonants
[ "Aspirated_consonant\n\nWu Chinese has a three-way distinction in stops and affricates: /p pʰ b/. In addition to aspirated and unaspirated consonants, there is a series of muddy consonants, like /b/. These are pronounced with slack or breathy voice: that is, they are weakly voiced. Muddy consonants as initial cause...
56e06d44231d4119001ac106
What kind of voice are muddy consonants pronounced with?
slack or breathy
[ "Aspirated_consonant\n\nWu Chinese has a three-way distinction in stops and affricates: /p pʰ b/. In addition to aspirated and unaspirated consonants, there is a series of muddy consonants, like /b/. These are pronounced with slack or breathy voice: that is, they are weakly voiced. Muddy consonants as initial cause...
56e06dca231d4119001ac10d
How many distinctions in stops do languages like Bengali and Hindi have?
four
[ "Aspirated_consonant\n\nMany Indo-Aryan languages have aspirated stops. Sanskrit, Hindi, Bengali, Marathi, and Gujarati have a four-way distinction in stops: voiceless, aspirated, voiced, and breathy-voiced or voiced aspirated, such as /p pʰ b bʱ/. Punjabi has lost breathy-voiced consonants, which resulted in a ton...
56e06dca231d4119001ac10f
What is another term for voice-aspirated?
breathy-voiced
[ "Aspirated_consonant\n\nMany Indo-Aryan languages have aspirated stops. Sanskrit, Hindi, Bengali, Marathi, and Gujarati have a four-way distinction in stops: voiceless, aspirated, voiced, and breathy-voiced or voiced aspirated, such as /p pʰ b bʱ/. Punjabi has lost breathy-voiced consonants, which resulted in a ton...
56e06dca231d4119001ac111
Which distinction has Punjabi lost?
breathy-voiced consonants
[ "Aspirated_consonant\n\nMany Indo-Aryan languages have aspirated stops. Sanskrit, Hindi, Bengali, Marathi, and Gujarati have a four-way distinction in stops: voiceless, aspirated, voiced, and breathy-voiced or voiced aspirated, such as /p pʰ b bʱ/. Punjabi has lost breathy-voiced consonants, which resulted in a ton...
56e06eee231d4119001ac117
Telegu, Kannada and others are considered to be some of the what languages?
Dravidian
[ "Aspirated_consonant\n\nSome of the Dravidian languages, such as Telugu, Tamil, Malayalam, and Kannada, have a distinction between voiced and voiceless, aspirated and unaspirated only in loanwords from Indo-Aryan languages. In native Dravidian words, there is no distinction between these categories and stops are un...
56e06eee231d4119001ac119
What has no distinction between the categories of voiced, voiceless, aspirated and unaspirated?
native Dravidian words
[ "Aspirated_consonant\n\nSome of the Dravidian languages, such as Telugu, Tamil, Malayalam, and Kannada, have a distinction between voiced and voiceless, aspirated and unaspirated only in loanwords from Indo-Aryan languages. In native Dravidian words, there is no distinction between these categories and stops are un...
56e070687aa994140058e4c3
What language has two-way distinctions between aspirated and voiced?
Western Armenian
[ "Aspirated_consonant\n\nWestern Armenian has a two-way distinction between aspirated and voiced: /tʰ d/. Western Armenian aspirated /tʰ/ corresponds to Eastern Armenian aspirated /tʰ/ and voiced /d/, and Western voiced /d/ corresponds to Eastern voiceless /t/." ]
56e070687aa994140058e4c4
Western Armenian /tʰ/ compares to eastern Armenian /tʰ/ and what?
/d/
[ "Aspirated_consonant\n\nWestern Armenian has a two-way distinction between aspirated and voiced: /tʰ d/. Western Armenian aspirated /tʰ/ corresponds to Eastern Armenian aspirated /tʰ/ and voiced /d/, and Western voiced /d/ corresponds to Eastern voiceless /t/." ]
56e070687aa994140058e4c5
The Western Armenian voiced /d/ compares to the Eastern Armenian voiceless what?
/t/
[ "Aspirated_consonant\n\nWestern Armenian has a two-way distinction between aspirated and voiced: /tʰ d/. Western Armenian aspirated /tʰ/ corresponds to Eastern Armenian aspirated /tʰ/ and voiced /d/, and Western voiced /d/ corresponds to Eastern voiceless /t/." ]
56e072537aa994140058e4c9
Early Greek (before Koine) have been redone with what?
aspirated stops.
[ "Aspirated_consonant\n\nSome forms of Greek before the Koine Greek period are reconstructed as having aspirated stops. The Classical Attic dialect of Ancient Greek had a three-way distinction in stops like Eastern Armenian: /t tʰ d/. These stops were called ψιλά, δασέα, μέσα \"thin, thick, middle\" by Koine Greek g...
56e072537aa994140058e4ca
What Greek dialect had three-way stop distinction like Eastern Armenian?
Classical Attic
[ "Aspirated_consonant\n\nSome forms of Greek before the Koine Greek period are reconstructed as having aspirated stops. The Classical Attic dialect of Ancient Greek had a three-way distinction in stops like Eastern Armenian: /t tʰ d/. These stops were called ψιλά, δασέα, μέσα \"thin, thick, middle\" by Koine Greek g...
56e072537aa994140058e4cc
Who referred to the Classical Attic dialect stops by the three distinctions?
Greek grammarians
[ "Aspirated_consonant\n\nSome forms of Greek before the Koine Greek period are reconstructed as having aspirated stops. The Classical Attic dialect of Ancient Greek had a three-way distinction in stops like Eastern Armenian: /t tʰ d/. These stops were called ψιλά, δασέα, μέσα \"thin, thick, middle\" by Koine Greek g...
56e072b57aa994140058e4d2
What is the representation for the three places of articulation?
/pʰ tʰ kʰ/
[ "Aspirated_consonant\n\nThere were aspirated stops at three places of articulation: labial, coronal, and velar /pʰ tʰ kʰ/. Earlier Greek, represented by Mycenaean Greek, likely had a labialized velar aspirated stop /kʷʰ/, which later became labial, coronal, or velar depending on dialect and phonetic environment." ]
56e072b57aa994140058e4d3
Earlier Greek was represented by what?
Mycenaean Greek
[ "Aspirated_consonant\n\nThere were aspirated stops at three places of articulation: labial, coronal, and velar /pʰ tʰ kʰ/. Earlier Greek, represented by Mycenaean Greek, likely had a labialized velar aspirated stop /kʷʰ/, which later became labial, coronal, or velar depending on dialect and phonetic environment." ]
56e072b57aa994140058e4d4
Whether a stop was labial, coronal or velar depended on what two things?
dialect and phonetic environment
[ "Aspirated_consonant\n\nThere were aspirated stops at three places of articulation: labial, coronal, and velar /pʰ tʰ kʰ/. Earlier Greek, represented by Mycenaean Greek, likely had a labialized velar aspirated stop /kʷʰ/, which later became labial, coronal, or velar depending on dialect and phonetic environment." ]
56e073267aa994140058e4d9
Dialects such as Aeolic and Doric had how many distinctions that were the same at one point in time?
three
[ "Aspirated_consonant\n\nThe other Ancient Greek dialects, Ionic, Doric, Aeolic, and Arcadocypriot, likely had the same three-way distinction at one point, but Doric seems to have had a fricative in place of /tʰ/ in the Classical period, and the Ionic and Aeolic dialects sometimes lost aspiration (psilosis)." ]
56e073267aa994140058e4da
Which two dialects lost aspiration at times?
Ionic and Aeolic
[ "Aspirated_consonant\n\nThe other Ancient Greek dialects, Ionic, Doric, Aeolic, and Arcadocypriot, likely had the same three-way distinction at one point, but Doric seems to have had a fricative in place of /tʰ/ in the Classical period, and the Ionic and Aeolic dialects sometimes lost aspiration (psilosis)." ]
56e073267aa994140058e4db
Rather than /tʰ/, what did the Doric dialect have in place during the Classical period?
fricative
[ "Aspirated_consonant\n\nThe other Ancient Greek dialects, Ionic, Doric, Aeolic, and Arcadocypriot, likely had the same three-way distinction at one point, but Doric seems to have had a fricative in place of /tʰ/ in the Classical period, and the Ionic and Aeolic dialects sometimes lost aspiration (psilosis)." ]
56e073d0231d4119001ac177
Attic Greek lenited to what?
voiceless and voiced fricatives
[ "Aspirated_consonant\n\nLater, during the Koine Greek period, the aspirated and voiceless stops /tʰ d/ of Attic Greek lenited to voiceless and voiced fricatives, yielding /θ ð/ in Medieval and Modern Greek." ]
56e073d0231d4119001ac179
The lenited Attic Greek yielded /θ ð/ in what periods?
Medieval and Modern Greek
[ "Aspirated_consonant\n\nLater, during the Koine Greek period, the aspirated and voiceless stops /tʰ d/ of Attic Greek lenited to voiceless and voiced fricatives, yielding /θ ð/ in Medieval and Modern Greek." ]
56e074547aa994140058e4fd
Aspiration may refer to a sound change of what?
debuccalization
[ "Aspirated_consonant\n\nThe term aspiration sometimes refers to the sound change of debuccalization, in which a consonant is lenited (weakened) to become a glottal stop or fricative [ʔ h ɦ]." ]
56e074547aa994140058e4fe
Debuccalization is when consonants are weakened to become what?
glottal stop or fricative
[ "Aspirated_consonant\n\nThe term aspiration sometimes refers to the sound change of debuccalization, in which a consonant is lenited (weakened) to become a glottal stop or fricative [ʔ h ɦ]." ]
56e074547aa994140058e4ff
What is another term for a consonant being weakened?
lenited
[ "Aspirated_consonant\n\nThe term aspiration sometimes refers to the sound change of debuccalization, in which a consonant is lenited (weakened) to become a glottal stop or fricative [ʔ h ɦ]." ]
56e075f87aa994140058e509
What is breathy voice?
a type of phonation or vibration of the vocal folds
[ "Aspirated_consonant\n\nSo-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\"...
56e075f87aa994140058e50d
The ⟨bʰ⟩ in the Indo-Aryan languages is better transcribed how for breathy voice?
⟨b̤⟩, with the diacritic
[ "Aspirated_consonant\n\nSo-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\"...
56e0769d7aa994140058e513
What do some linguists restrict the double-dot subscript ⟨◌̤⟩ to?
murmured sonorants
[ "Aspirated_consonant\n\nSome 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." ]
56e0769d7aa994140058e514
What are, according to the text, murmured for their duration?
vowels and nasals
[ "Aspirated_consonant\n\nSome 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." ]
56e0769d7aa994140058e515
What uses the ⟨◌ʱ⟩?
breathy-voiced release of obstruents.
[ "Aspirated_consonant\n\nSome 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." ]
56e0711b231d4119001ac141
What is hydrogens chemical symbol?
H
[ "Hydrogen\n\nHydrogen 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 bary...
56e0711b231d4119001ac142
What is the atomic number used for hydrogen?
1
[ "Hydrogen\n\nHydrogen 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 bary...
56e0711b231d4119001ac143
What is the atomic weight for hydrogen?
7000100794000000000♠1.00794 u
[ "Hydrogen\n\nHydrogen 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 bary...
56e0711b231d4119001ac144
What element is considered the lightest?
Hydrogen
[ "Hydrogen\n\nHydrogen 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 bary...
56e0733b231d4119001ac16d
What form can you find hydrogen is on Earth?
molecular
[ "Hydrogen\n\nThe 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 comp...
56e0733b231d4119001ac16e
What is the molecular make-up of hydrogen?
H2
[ "Hydrogen\n\nThe 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 comp...
56e0733b231d4119001ac16f
What are three properties of hydrogen at normal temperature and normal pressure?
colorless, odorless, tasteless
[ "Hydrogen\n\nThe 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 comp...
56e0733b231d4119001ac170
What charge does hydrogen display in ionic compounds when it is called a hydride?
negative
[ "Hydrogen\n\nThe 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 comp...
56e0733b231d4119001ac171
What field of study has hydrogen and it's properties played a key role in development?
quantum mechanics
[ "Hydrogen\n\nThe 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 comp...
56e073a47aa994140058e4df
When was hydrogen gas artificially produced for the first time?
early 16th century
[ "Hydrogen\n\nHydrogen 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, hydr...
56e073a47aa994140058e4e1
Who first recognized that hydrogen was a discrete substance?
Henry Cavendish
[ "Hydrogen\n\nHydrogen 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, hydr...
56e073a47aa994140058e4e2
When it is burned what does hydrogen make?
water
[ "Hydrogen\n\nHydrogen 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, hydr...
56e073a47aa994140058e4e3
What is the Greek translation for hydrogen?
water-former
[ "Hydrogen\n\nHydrogen 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, hydr...
56e074137aa994140058e4f5
What market primarily uses ammonia production?
the fertilizer market
[ "Hydrogen\n\nIndustrial 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)...
56e074137aa994140058e4f7
Name a process that uses fossil fuels along with hydrogen.
hydrocracking
[ "Hydrogen\n\nIndustrial 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)...
56e07476231d4119001ac17f
For hydrogen what is the enthalpy of combustion?
286 kJ/mol
[ "Hydrogen\n\nHydrogen 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:" ]
56e07476231d4119001ac180
What are two forms of hydrogen gas?
dihydrogen or molecular hydrogen
[ "Hydrogen\n\nHydrogen 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:" ]
56e07476231d4119001ac181
Which element has a enthalpy of combustion at −286 kJ/mol?
Hydrogen
[ "Hydrogen\n\nHydrogen 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:" ]
56e074de231d4119001ac18a
What kind of light do hydrogen-oxygen flames make?
ultraviolet light
[ "Hydrogen\n\nHydrogen 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-oxyg...
56e074de231d4119001ac18b
What caused the Hindenburg to explode?
hydrogen combustion
[ "Hydrogen\n\nHydrogen 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-oxyg...
56e0758e7aa994140058e503
What are two other dangerous acids?
hydrogen chloride and hydrogen fluoride
[ "Hydrogen\n\nH2 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." ]
56e0758e7aa994140058e505
What temperature does hydrogen react with these elements?
room temperature
[ "Hydrogen\n\nH2 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." ]
56e077207aa994140058e519
What model id used to calculate energy levels of hydrogen?
Bohr model
[ "Hydrogen\n\nThe 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 an...
56e077207aa994140058e51a
What attracts planets and celestial items?
gravity
[ "Hydrogen\n\nThe 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 an...
56e077207aa994140058e51b
What does the electromagnetic force attract to one another?
electrons and protons
[ "Hydrogen\n\nThe 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 an...
56e081487aa994140058e588
What kind of movement does the electron not have in ground state?
angular
[ "Hydrogen\n\nA 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 allo...
56e087957aa994140058e5c1
How many different spin isomers exist?
2
[ "Hydrogen\n\nThere 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 a...
56e087957aa994140058e5c2
What state are the protons in when in the orthohydrogen form?
triplet state
[ "Hydrogen\n\nThere 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 a...
56e087957aa994140058e5c3
When hydrogen gas is in standard temperature and pressure, what form is it considered in>
normal
[ "Hydrogen\n\nThere 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 a...
56e087957aa994140058e5c4
What percent of para form does hydrogen gas contain?
25%
[ "Hydrogen\n\nThere 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 a...
56e087957aa994140058e5c5
What percent of ortho form does hydrogen gas contain?
75%
[ "Hydrogen\n\nThere 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 a...
56e088e17aa994140058e5ce
What are some catalysts used in hydrogen cooling
ferric oxide, activated carbon, platinized asbestos, rare earth metals, uranium compounds, chromic oxide, or some nickel compounds
[ "Hydrogen\n\nThe uncatalyzed interconversion between para and ortho H2 increases with increasing temperature; thus rapidly condensed H2 contains large quantities of the high-energy ortho form that converts to the para form very slowly. The ortho/para ratio in condensed H2 is an important consideration in the prepar...
56e08a18231d4119001ac290
What ind of charge does hydrogen take when mixed with electronegative particles?
positive charge
[ "Hydrogen\n\nWhile 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 f...
56e08a18231d4119001ac291
What type of charge does hydrogen take when combined with a metal?
negative
[ "Hydrogen\n\nWhile 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 f...
56e08a18231d4119001ac292
When hydrogen forms with a metal, what is the compound called?
hydrides
[ "Hydrogen\n\nWhile 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 f...
56e08a18231d4119001ac293
Is H2 reactive in standard conditions?
not
[ "Hydrogen\n\nWhile 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 f...
56e08b457aa994140058e5e3
What is the form of hydrogen and carbon called?
hydrocarbons
[ "Hydrogen\n\nHydrogen 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...
56e08b457aa994140058e5e4
What is the form of hydrogen and heteroatoms called?
organic compounds
[ "Hydrogen\n\nHydrogen 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...
56e08b457aa994140058e5e5
What is the study of organic compounds properties known as?
organic chemistry
[ "Hydrogen\n\nHydrogen 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...
56e08b457aa994140058e5e6
What is the study of living organisms known as?
biochemistry
[ "Hydrogen\n\nHydrogen 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...
56e08b457aa994140058e5e7
Organic compounds are only required to conatin what?
carbon
[ "Hydrogen\n\nHydrogen 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...
56e090e27aa994140058e5ee
Who suggested that hydride anions existed?character does the H atom have in a hydride?
Gilbert N. Lewis
[ "Hydrogen\n\nCompounds 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...
56e090e27aa994140058e5f0
What group of hydrides is BEH considered polymeric?
group II
[ "Hydrogen\n\nCompounds 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...
56e0914c7aa994140058e5f7
How many binary borane hydrides are known?
over 100
[ "Hydrogen\n\nAlthough 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 co...
56e0914c7aa994140058e5f8
How many binary aluminum hydrides are there?
1
[ "Hydrogen\n\nAlthough 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 co...
56e092177aa994140058e5fd
What chemistry do hydrides serve as bridging ligands?
inorganic chemistry
[ "Hydrogen\n\nIn 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." ]