id
stringlengths
24
24
question
stringlengths
1
270
answer
stringlengths
1
239
documents
listlengths
1
1
572925d76aef051400154ab9
What kind of glass are containers made from?
soda-lime glass
[ "Glass\n\nThe most familiar, and historically the oldest, types of glass are \"silicate glasses\" based on the chemical compound silica (silicon dioxide, or quartz), the primary constituent of sand. The term glass, in popular usage, is often used to refer only to this type of material, which is familiar from use as...
572925d76aef051400154aba
What is sand mostly made of?
silica
[ "Glass\n\nThe most familiar, and historically the oldest, types of glass are \"silicate glasses\" based on the chemical compound silica (silicon dioxide, or quartz), the primary constituent of sand. The term glass, in popular usage, is often used to refer only to this type of material, which is familiar from use as...
572925d76aef051400154abb
What can a very strong and transparent glass be made from?
pure silica
[ "Glass\n\nThe most familiar, and historically the oldest, types of glass are \"silicate glasses\" based on the chemical compound silica (silicon dioxide, or quartz), the primary constituent of sand. The term glass, in popular usage, is often used to refer only to this type of material, which is familiar from use as...
572925d76aef051400154abc
What types of glass is the word commonly used to mean?
silicate glasses
[ "Glass\n\nThe most familiar, and historically the oldest, types of glass are \"silicate glasses\" based on the chemical compound silica (silicon dioxide, or quartz), the primary constituent of sand. The term glass, in popular usage, is often used to refer only to this type of material, which is familiar from use as...
572927efaf94a219006aa117
What does glass lack, allowing it to be transparent?
internal subdivisions
[ "Glass\n\nGlass is in widespread use largely due to the production of glass compositions that are transparent to visible light. In contrast, polycrystalline materials do not generally transmit visible light. The individual crystallites may be transparent, but their facets (grain boundaries) reflect or scatter light...
572927efaf94a219006aa118
What force gives glass its surface texture?
surface tension
[ "Glass\n\nGlass is in widespread use largely due to the production of glass compositions that are transparent to visible light. In contrast, polycrystalline materials do not generally transmit visible light. The individual crystallites may be transparent, but their facets (grain boundaries) reflect or scatter light...
572927efaf94a219006aa119
What, in contrast to glass, doesn't let light pass through?
polycrystalline materials
[ "Glass\n\nGlass is in widespread use largely due to the production of glass compositions that are transparent to visible light. In contrast, polycrystalline materials do not generally transmit visible light. The individual crystallites may be transparent, but their facets (grain boundaries) reflect or scatter light...
572927efaf94a219006aa11a
What type of glass absorbs some light?
colored
[ "Glass\n\nGlass is in widespread use largely due to the production of glass compositions that are transparent to visible light. In contrast, polycrystalline materials do not generally transmit visible light. The individual crystallites may be transparent, but their facets (grain boundaries) reflect or scatter light...
57292a1e1d046914007790fb
What kind of glass exists in nature?
obsidian
[ "Glass\n\nNaturally occurring glass, especially the volcanic glass obsidian, has been used by many Stone Age societies across the globe for the production of sharp cutting tools and, due to its limited source areas, was extensively traded. But in general, archaeological evidence suggests that the first true glass w...
57292a1e1d046914007790fc
Obsidian is what type of glass?
volcanic
[ "Glass\n\nNaturally occurring glass, especially the volcanic glass obsidian, has been used by many Stone Age societies across the globe for the production of sharp cutting tools and, due to its limited source areas, was extensively traded. But in general, archaeological evidence suggests that the first true glass w...
57292a1e1d046914007790fd
What was obsidian used to make in prehistoric times?
cutting tools
[ "Glass\n\nNaturally occurring glass, especially the volcanic glass obsidian, has been used by many Stone Age societies across the globe for the production of sharp cutting tools and, due to its limited source areas, was extensively traded. But in general, archaeological evidence suggests that the first true glass w...
57292a1e1d046914007790fe
When are the oldest beads thought to have been made?
mid third millennium BCE
[ "Glass\n\nNaturally occurring glass, especially the volcanic glass obsidian, has been used by many Stone Age societies across the globe for the production of sharp cutting tools and, due to its limited source areas, was extensively traded. But in general, archaeological evidence suggests that the first true glass w...
57292a1e1d046914007790ff
What glass-like material is made with a method related to glazing?
faience
[ "Glass\n\nNaturally occurring glass, especially the volcanic glass obsidian, has been used by many Stone Age societies across the globe for the production of sharp cutting tools and, due to its limited source areas, was extensively traded. But in general, archaeological evidence suggests that the first true glass w...
572936abaf94a219006aa1a3
What can give glass a faint green tinge?
iron(II) oxide
[ "Glass\n\nColor in glass may be obtained by addition of electrically charged ions (or color centers) that are homogeneously distributed, and by precipitation of finely dispersed particles (such as in photochromic glasses). Ordinary soda-lime glass appears colorless to the naked eye when it is thin, although iron(II...
572936abaf94a219006aa1a4
What can prevent a green color in glass?
Manganese dioxide
[ "Glass\n\nColor in glass may be obtained by addition of electrically charged ions (or color centers) that are homogeneously distributed, and by precipitation of finely dispersed particles (such as in photochromic glasses). Ordinary soda-lime glass appears colorless to the naked eye when it is thin, although iron(II...
572936abaf94a219006aa1a5
What other than additives can give glass a yellow color?
reducing combustion atmosphere
[ "Glass\n\nColor in glass may be obtained by addition of electrically charged ions (or color centers) that are homogeneously distributed, and by precipitation of finely dispersed particles (such as in photochromic glasses). Ordinary soda-lime glass appears colorless to the naked eye when it is thin, although iron(II...
572936abaf94a219006aa1a6
What chemical compounds can make glass nearly black?
iron polysulfides
[ "Glass\n\nColor in glass may be obtained by addition of electrically charged ions (or color centers) that are homogeneously distributed, and by precipitation of finely dispersed particles (such as in photochromic glasses). Ordinary soda-lime glass appears colorless to the naked eye when it is thin, although iron(II...
572936abaf94a219006aa1a7
Charged ions can be used to produce what in glass?
Color
[ "Glass\n\nColor in glass may be obtained by addition of electrically charged ions (or color centers) that are homogeneously distributed, and by precipitation of finely dispersed particles (such as in photochromic glasses). Ordinary soda-lime glass appears colorless to the naked eye when it is thin, although iron(II...
57293c473f37b31900478151
What word does "glass" come from?
glesum
[ "Glass\n\nGlass remained a luxury material, and the disasters that overtook Late Bronze Age civilizations seem to have brought glass-making to a halt. Indigenous development of glass technology in South Asia may have begun in 1730 BCE. In ancient China, though, glassmaking seems to have a late start, compared to ce...
57293c473f37b31900478152
Where did glasswork begin relatively late?
China
[ "Glass\n\nGlass remained a luxury material, and the disasters that overtook Late Bronze Age civilizations seem to have brought glass-making to a halt. Indigenous development of glass technology in South Asia may have begun in 1730 BCE. In ancient China, though, glassmaking seems to have a late start, compared to ce...
57293c473f37b31900478153
In what year did glassmaking begin in Asia?
1730 BCE
[ "Glass\n\nGlass remained a luxury material, and the disasters that overtook Late Bronze Age civilizations seem to have brought glass-making to a halt. Indigenous development of glass technology in South Asia may have begun in 1730 BCE. In ancient China, though, glassmaking seems to have a late start, compared to ce...
57293c473f37b31900478154
What city was a center of glass production for the Romans?
Trier
[ "Glass\n\nGlass remained a luxury material, and the disasters that overtook Late Bronze Age civilizations seem to have brought glass-making to a halt. Indigenous development of glass technology in South Asia may have begun in 1730 BCE. In ancient China, though, glassmaking seems to have a late start, compared to ce...
57293c473f37b31900478155
In what current country is Trier located?
Germany
[ "Glass\n\nGlass remained a luxury material, and the disasters that overtook Late Bronze Age civilizations seem to have brought glass-making to a halt. Indigenous development of glass technology in South Asia may have begun in 1730 BCE. In ancient China, though, glassmaking seems to have a late start, compared to ce...
5729450a6aef051400154c2e
When did stained glass make a big comeback?
19th-century
[ "Glass\n\nGlass was used extensively during the Middle Ages. Anglo-Saxon glass has been found across England during archaeological excavations of both settlement and cemetery sites. Glass in the Anglo-Saxon period was used in the manufacture of a range of objects including vessels, beads, windows and was also used ...
5729450a6aef051400154c2f
When did stained glass begin to be used for places of worship?
10th-century
[ "Glass\n\nGlass was used extensively during the Middle Ages. Anglo-Saxon glass has been found across England during archaeological excavations of both settlement and cemetery sites. Glass in the Anglo-Saxon period was used in the manufacture of a range of objects including vessels, beads, windows and was also used ...
5729450a6aef051400154c30
When did big windows of stained glass become less common?
the Renaissance
[ "Glass\n\nGlass was used extensively during the Middle Ages. Anglo-Saxon glass has been found across England during archaeological excavations of both settlement and cemetery sites. Glass in the Anglo-Saxon period was used in the manufacture of a range of objects including vessels, beads, windows and was also used ...
5729450a6aef051400154c31
What 13th-century building is an example of stained glass walls?
Sainte-Chapelle
[ "Glass\n\nGlass was used extensively during the Middle Ages. Anglo-Saxon glass has been found across England during archaeological excavations of both settlement and cemetery sites. Glass in the Anglo-Saxon period was used in the manufacture of a range of objects including vessels, beads, windows and was also used ...
5729450a6aef051400154c32
What did technological changes allow regular homes to have?
larger windows
[ "Glass\n\nGlass was used extensively during the Middle Ages. Anglo-Saxon glass has been found across England during archaeological excavations of both settlement and cemetery sites. Glass in the Anglo-Saxon period was used in the manufacture of a range of objects including vessels, beads, windows and was also used ...
572946226aef051400154c38
What type of glass is used in cars?
laminated
[ "Glass\n\nIn the 20th century, new types of glass such as laminated glass, reinforced glass and glass bricks have increased the use of glass as a building material and resulted in new applications of glass. Multi-storey buildings are frequently constructed with curtain walls made almost entirely of glass. Similarly...
572946226aef051400154c39
When did eyeglasses originate?
late Middle Ages
[ "Glass\n\nIn the 20th century, new types of glass such as laminated glass, reinforced glass and glass bricks have increased the use of glass as a building material and resulted in new applications of glass. Multi-storey buildings are frequently constructed with curtain walls made almost entirely of glass. Similarly...
572946226aef051400154c3a
The walls of skyscrapers are often made of what material?
glass
[ "Glass\n\nIn the 20th century, new types of glass such as laminated glass, reinforced glass and glass bricks have increased the use of glass as a building material and resulted in new applications of glass. Multi-storey buildings are frequently constructed with curtain walls made almost entirely of glass. Similarly...
572946226aef051400154c3b
What type of power systems use glass?
solar
[ "Glass\n\nIn the 20th century, new types of glass such as laminated glass, reinforced glass and glass bricks have increased the use of glass as a building material and resulted in new applications of glass. Multi-storey buildings are frequently constructed with curtain walls made almost entirely of glass. Similarly...
572946226aef051400154c3c
What type of scientists rely on glass for distant observations?
astronomers
[ "Glass\n\nIn the 20th century, new types of glass such as laminated glass, reinforced glass and glass bricks have increased the use of glass as a building material and resulted in new applications of glass. Multi-storey buildings are frequently constructed with curtain walls made almost entirely of glass. Similarly...
572947c3af94a219006aa247
What famous lampmaker used glass?
Louis Comfort Tiffany
[ "Glass\n\nFrom the 19th century, there was a revival in many ancient glass-making techniques including cameo glass, achieved for the first time since the Roman Empire and initially mostly used for pieces in a neo-classical style. The Art Nouveau movement made great use of glass, with René Lalique, Émile Gallé, and ...
572947c3af94a219006aa248
When did glassworkers begin to consider their products fine art?
1960
[ "Glass\n\nFrom the 19th century, there was a revival in many ancient glass-making techniques including cameo glass, achieved for the first time since the Roman Empire and initially mostly used for pieces in a neo-classical style. The Art Nouveau movement made great use of glass, with René Lalique, Émile Gallé, and ...
572947c3af94a219006aa249
What type of glass did many Art Nouveau artists use?
cameo glass
[ "Glass\n\nFrom the 19th century, there was a revival in many ancient glass-making techniques including cameo glass, achieved for the first time since the Roman Empire and initially mostly used for pieces in a neo-classical style. The Art Nouveau movement made great use of glass, with René Lalique, Émile Gallé, and ...
572947c3af94a219006aa24a
When did mass production of glass art begin?
early 20th-century
[ "Glass\n\nFrom the 19th century, there was a revival in many ancient glass-making techniques including cameo glass, achieved for the first time since the Roman Empire and initially mostly used for pieces in a neo-classical style. The Art Nouveau movement made great use of glass, with René Lalique, Émile Gallé, and ...
572947c3af94a219006aa24b
What early civilization made cameo glass?
Roman Empire
[ "Glass\n\nFrom the 19th century, there was a revival in many ancient glass-making techniques including cameo glass, achieved for the first time since the Roman Empire and initially mostly used for pieces in a neo-classical style. The Art Nouveau movement made great use of glass, with René Lalique, Émile Gallé, and ...
572964476aef051400154de6
What makes glass melt at a lower temperature?
lead(II) oxide
[ "Glass\n\nAddition of lead(II) oxide lowers melting point, lowers viscosity of the melt, and increases refractive index. Lead oxide also facilitates solubility of other metal oxides and is used in colored glasses. The viscosity decrease of lead glass melt is very significant (roughly 100 times in comparison with so...
572964476aef051400154de7
How much less viscous is lead glass compared with soda glass?
100 times
[ "Glass\n\nAddition of lead(II) oxide lowers melting point, lowers viscosity of the melt, and increases refractive index. Lead oxide also facilitates solubility of other metal oxides and is used in colored glasses. The viscosity decrease of lead glass melt is very significant (roughly 100 times in comparison with so...
572964476aef051400154de8
Pb2+ causes lead glass to have what?
high electrical resistance
[ "Glass\n\nAddition of lead(II) oxide lowers melting point, lowers viscosity of the melt, and increases refractive index. Lead oxide also facilitates solubility of other metal oxides and is used in colored glasses. The viscosity decrease of lead glass melt is very significant (roughly 100 times in comparison with so...
572964476aef051400154de9
Lead oxide makes it easier to dissolve what?
other metal oxides
[ "Glass\n\nAddition of lead(II) oxide lowers melting point, lowers viscosity of the melt, and increases refractive index. Lead oxide also facilitates solubility of other metal oxides and is used in colored glasses. The viscosity decrease of lead glass melt is very significant (roughly 100 times in comparison with so...
57296639af94a219006aa389
What components of glass for networks?
silicon, boron, germanium
[ "Glass\n\nThere are three classes of components for oxide glasses: network formers, intermediates, and modifiers. The network formers (silicon, boron, germanium) form a highly cross-linked network of chemical bonds. The intermediates (titanium, aluminium, zirconium, beryllium, magnesium, zinc) can act as both netwo...
57296639af94a219006aa38a
What type of components change the network's shape?
modifiers
[ "Glass\n\nThere are three classes of components for oxide glasses: network formers, intermediates, and modifiers. The network formers (silicon, boron, germanium) form a highly cross-linked network of chemical bonds. The intermediates (titanium, aluminium, zirconium, beryllium, magnesium, zinc) can act as both netwo...
57296639af94a219006aa38b
What type of component can both make and change networks?
intermediates
[ "Glass\n\nThere are three classes of components for oxide glasses: network formers, intermediates, and modifiers. The network formers (silicon, boron, germanium) form a highly cross-linked network of chemical bonds. The intermediates (titanium, aluminium, zirconium, beryllium, magnesium, zinc) can act as both netwo...
57296639af94a219006aa38c
What type of chemical attachment connects ions to the network?
covalent bond
[ "Glass\n\nThere are three classes of components for oxide glasses: network formers, intermediates, and modifiers. The network formers (silicon, boron, germanium) form a highly cross-linked network of chemical bonds. The intermediates (titanium, aluminium, zirconium, beryllium, magnesium, zinc) can act as both netwo...
57296766af94a219006aa3a3
What component gives glass the ability to conduct electricity?
alkali metal ions
[ "Glass\n\nThe alkali metal ions are small and mobile; their presence in glass allows a degree of electrical conductivity, especially in molten state or at high temperature. Their mobility decreases the chemical resistance of the glass, allowing leaching by water and facilitating corrosion. Alkaline earth ions, with...
57296766af94a219006aa3a4
How can glass be prevented from corroding?
dealkalization
[ "Glass\n\nThe alkali metal ions are small and mobile; their presence in glass allows a degree of electrical conductivity, especially in molten state or at high temperature. Their mobility decreases the chemical resistance of the glass, allowing leaching by water and facilitating corrosion. Alkaline earth ions, with...
57296766af94a219006aa3a5
What types of ions does typical glass have?
alkali and alkaline earth ions
[ "Glass\n\nThe alkali metal ions are small and mobile; their presence in glass allows a degree of electrical conductivity, especially in molten state or at high temperature. Their mobility decreases the chemical resistance of the glass, allowing leaching by water and facilitating corrosion. Alkaline earth ions, with...
57296766af94a219006aa3a6
Reaction with what causes dealkalization?
sulfur or fluorine compounds
[ "Glass\n\nThe alkali metal ions are small and mobile; their presence in glass allows a degree of electrical conductivity, especially in molten state or at high temperature. Their mobility decreases the chemical resistance of the glass, allowing leaching by water and facilitating corrosion. Alkaline earth ions, with...
57296766af94a219006aa3a7
What can alkaline ions in glass harm, in addition to electrical resistance?
loss tangent
[ "Glass\n\nThe alkali metal ions are small and mobile; their presence in glass allows a degree of electrical conductivity, especially in molten state or at high temperature. Their mobility decreases the chemical resistance of the glass, allowing leaching by water and facilitating corrosion. Alkaline earth ions, with...
5729689c3f37b31900478343
What material is useful in glassmaking because of its slow evaporation?
sodium selenite
[ "Glass\n\nNew chemical glass compositions or new treatment techniques can be initially investigated in small-scale laboratory experiments. The raw materials for laboratory-scale glass melts are often different from those used in mass production because the cost factor has a low priority. In the laboratory mostly pu...
5729689c3f37b31900478344
What containers are used for melting?
platinum crucibles
[ "Glass\n\nNew chemical glass compositions or new treatment techniques can be initially investigated in small-scale laboratory experiments. The raw materials for laboratory-scale glass melts are often different from those used in mass production because the cost factor has a low priority. In the laboratory mostly pu...
5729689c3f37b31900478345
Why are different materials used in a lab than are used in factory production?
the cost factor has a low priority
[ "Glass\n\nNew chemical glass compositions or new treatment techniques can be initially investigated in small-scale laboratory experiments. The raw materials for laboratory-scale glass melts are often different from those used in mass production because the cost factor has a low priority. In the laboratory mostly pu...
5729689c3f37b31900478346
What is the reason for crushing the glass and melting it again?
homogeneity
[ "Glass\n\nNew chemical glass compositions or new treatment techniques can be initially investigated in small-scale laboratory experiments. The raw materials for laboratory-scale glass melts are often different from those used in mass production because the cost factor has a low priority. In the laboratory mostly pu...
5729689c3f37b31900478347
Why is glass annealed?
to prevent breakage
[ "Glass\n\nNew chemical glass compositions or new treatment techniques can be initially investigated in small-scale laboratory experiments. The raw materials for laboratory-scale glass melts are often different from those used in mass production because the cost factor has a low priority. In the laboratory mostly pu...
57296ab01d046914007793e7
Who coined the term "splat cooling"?
W. Klement
[ "Glass\n\nIn the past, small batches of amorphous metals with high surface area configurations (ribbons, wires, films, etc.) have been produced through the implementation of extremely rapid rates of cooling. This was initially termed \"splat cooling\" by doctoral student W. Klement at Caltech, who showed that cooli...
57296ab01d046914007793e8
What are thick alloys made in layers called?
bulk metallic glasses
[ "Glass\n\nIn the past, small batches of amorphous metals with high surface area configurations (ribbons, wires, films, etc.) have been produced through the implementation of extremely rapid rates of cooling. This was initially termed \"splat cooling\" by doctoral student W. Klement at Caltech, who showed that cooli...
57296ab01d046914007793e9
What does Liquidmetal Technologies use for their alloys?
zirconium
[ "Glass\n\nIn the past, small batches of amorphous metals with high surface area configurations (ribbons, wires, films, etc.) have been produced through the implementation of extremely rapid rates of cooling. This was initially termed \"splat cooling\" by doctoral student W. Klement at Caltech, who showed that cooli...
57296ab01d046914007793ea
What type of metal makes better alloys than traditional steel?
amorphous steel
[ "Glass\n\nIn the past, small batches of amorphous metals with high surface area configurations (ribbons, wires, films, etc.) have been produced through the implementation of extremely rapid rates of cooling. This was initially termed \"splat cooling\" by doctoral student W. Klement at Caltech, who showed that cooli...
57296ab01d046914007793eb
At what university was Klement a student?
Caltech
[ "Glass\n\nIn the past, small batches of amorphous metals with high surface area configurations (ribbons, wires, films, etc.) have been produced through the implementation of extremely rapid rates of cooling. This was initially termed \"splat cooling\" by doctoral student W. Klement at Caltech, who showed that cooli...
57296d396aef051400154e6a
Who showed that q-glass could be produced from a melt?
NIST researchers
[ "Glass\n\nIn 2004, NIST researchers presented evidence that an isotropic non-crystalline metallic phase (dubbed \"q-glass\") could be grown from the melt. This phase is the first phase, or \"primary phase,\" to form in the Al-Fe-Si system during rapid cooling. Interestingly, experimental evidence indicates that thi...
57296d396aef051400154e6b
What shows that there is an inner surface between glass and melt?
nucleation barrier
[ "Glass\n\nIn 2004, NIST researchers presented evidence that an isotropic non-crystalline metallic phase (dubbed \"q-glass\") could be grown from the melt. This phase is the first phase, or \"primary phase,\" to form in the Al-Fe-Si system during rapid cooling. Interestingly, experimental evidence indicates that thi...
57296d396aef051400154e6c
What is q-glass?
an isotropic non-crystalline metallic phase
[ "Glass\n\nIn 2004, NIST researchers presented evidence that an isotropic non-crystalline metallic phase (dubbed \"q-glass\") could be grown from the melt. This phase is the first phase, or \"primary phase,\" to form in the Al-Fe-Si system during rapid cooling. Interestingly, experimental evidence indicates that thi...
57296d396aef051400154e6d
What kind of microscope shows that q-glass grows as separate particles?
Transmission electron
[ "Glass\n\nIn 2004, NIST researchers presented evidence that an isotropic non-crystalline metallic phase (dubbed \"q-glass\") could be grown from the melt. This phase is the first phase, or \"primary phase,\" to form in the Al-Fe-Si system during rapid cooling. Interestingly, experimental evidence indicates that thi...
5729747d3f37b31900478405
What word means that ceramics don't absorb liquids?
vitreous
[ "Glass\n\nGlass-ceramic materials share many properties with both non-crystalline glass and crystalline ceramics. They are formed as a glass, and then partially crystallized by heat treatment. For example, the microstructure of whiteware ceramics frequently contains both amorphous and crystalline phases. Crystallin...
5729747d3f37b31900478406
What hardens glass-ceramics?
heat treatment
[ "Glass\n\nGlass-ceramic materials share many properties with both non-crystalline glass and crystalline ceramics. They are formed as a glass, and then partially crystallized by heat treatment. For example, the microstructure of whiteware ceramics frequently contains both amorphous and crystalline phases. Crystallin...
5729747d3f37b31900478407
What materials do glass ceramics have a lot in common with?
non-crystalline glass and crystalline ceramics
[ "Glass\n\nGlass-ceramic materials share many properties with both non-crystalline glass and crystalline ceramics. They are formed as a glass, and then partially crystallized by heat treatment. For example, the microstructure of whiteware ceramics frequently contains both amorphous and crystalline phases. Crystallin...
5729765a6aef051400154f48
How high of a temperature change can glass-ceramics handle?
1000 °C
[ "Glass\n\nThe term mainly refers to a mix of lithium and aluminosilicates that yields an array of materials with interesting thermomechanical properties. The most commercially important of these have the distinction of being impervious to thermal shock. Thus, glass-ceramics have become extremely useful for countert...
5729765a6aef051400154f49
Because of their heat resistance, glass-ceramics are especially suitable for what?
countertop cooking
[ "Glass\n\nThe term mainly refers to a mix of lithium and aluminosilicates that yields an array of materials with interesting thermomechanical properties. The most commercially important of these have the distinction of being impervious to thermal shock. Thus, glass-ceramics have become extremely useful for countert...
5729765a6aef051400154f4a
What is the most economically significant property of glass-ceramics?
impervious to thermal shock
[ "Glass\n\nThe term mainly refers to a mix of lithium and aluminosilicates that yields an array of materials with interesting thermomechanical properties. The most commercially important of these have the distinction of being impervious to thermal shock. Thus, glass-ceramics have become extremely useful for countert...
5729765a6aef051400154f4b
What ingredients give glass-ceramics its useful heat tolerance?
lithium and aluminosilicates
[ "Glass\n\nThe term mainly refers to a mix of lithium and aluminosilicates that yields an array of materials with interesting thermomechanical properties. The most commercially important of these have the distinction of being impervious to thermal shock. Thus, glass-ceramics have become extremely useful for countert...
5729765a6aef051400154f4c
What proportion of crystalline ceramics yields a product with a CTE of around 0?
~70%
[ "Glass\n\nThe term mainly refers to a mix of lithium and aluminosilicates that yields an array of materials with interesting thermomechanical properties. The most commercially important of these have the distinction of being impervious to thermal shock. Thus, glass-ceramics have become extremely useful for countert...
572977e11d046914007794c1
What were the areas at the center of an old sheet of glass called?
bull's-eyes
[ "Glass\n\nMass production of glass window panes in the early twentieth century caused a similar effect. In glass factories, molten glass was poured onto a large cooling table and allowed to spread. The resulting glass is thicker at the location of the pour, located at the center of the large sheet. These sheets wer...
572977e11d046914007794c2
In early 20th century glass production, the glass was thickest at what part of the sheet?
the center
[ "Glass\n\nMass production of glass window panes in the early twentieth century caused a similar effect. In glass factories, molten glass was poured onto a large cooling table and allowed to spread. The resulting glass is thicker at the location of the pour, located at the center of the large sheet. These sheets wer...
572977e11d046914007794c3
Currently window glass is made as what?
float glass
[ "Glass\n\nMass production of glass window panes in the early twentieth century caused a similar effect. In glass factories, molten glass was poured onto a large cooling table and allowed to spread. The resulting glass is thicker at the location of the pour, located at the center of the large sheet. These sheets wer...
572977e11d046914007794c4
How was the bull's-eye used?
for decorative effect
[ "Glass\n\nMass production of glass window panes in the early twentieth century caused a similar effect. In glass factories, molten glass was poured onto a large cooling table and allowed to spread. The resulting glass is thicker at the location of the pour, located at the center of the large sheet. These sheets wer...
572979896aef051400154f7e
What was the benefit of installing glass with the thick side at the bottom, in addition to avoiding water accumulation?
stability
[ "Glass\n\nThe observation that old windows are sometimes found to be thicker at the bottom than at the top is often offered as supporting evidence for the view that glass flows over a timescale of centuries, the assumption being that the glass has exhibited the liquid property of flowing from one shape to another. ...
572979896aef051400154f7f
Who used to make window panes?
glassblowers
[ "Glass\n\nThe observation that old windows are sometimes found to be thicker at the bottom than at the top is often offered as supporting evidence for the view that glass flows over a timescale of centuries, the assumption being that the glass has exhibited the liquid property of flowing from one shape to another. ...
572979896aef051400154f80
What is the name for the glassmaking method that involved spinning it into sheets?
crown glass process
[ "Glass\n\nThe observation that old windows are sometimes found to be thicker at the bottom than at the top is often offered as supporting evidence for the view that glass flows over a timescale of centuries, the assumption being that the glass has exhibited the liquid property of flowing from one shape to another. ...
572979896aef051400154f81
The thickness at the bottom of glass panes was once taken as evidence that glass had features of what state of matter?
liquid
[ "Glass\n\nThe observation that old windows are sometimes found to be thicker at the bottom than at the top is often offered as supporting evidence for the view that glass flows over a timescale of centuries, the assumption being that the glass has exhibited the liquid property of flowing from one shape to another. ...
572979896aef051400154f82
When does glass stop moving like a liquid?
once solidified
[ "Glass\n\nThe observation that old windows are sometimes found to be thicker at the bottom than at the top is often offered as supporting evidence for the view that glass flows over a timescale of centuries, the assumption being that the glass has exhibited the liquid property of flowing from one shape to another. ...
572982021d046914007794ef
How is "glass" defined in physics?
a solid formed by rapid melt quenching
[ "Glass\n\nIn physics, the standard definition of a glass (or vitreous solid) is a solid formed by rapid melt quenching. The term glass is often used to describe any amorphous solid that exhibits a glass transition temperature Tg. If the cooling is sufficiently rapid (relative to the characteristic crystallization t...
572982021d046914007794f0
What is the tendency to make a glass when cooled called?
glass-forming ability
[ "Glass\n\nIn physics, the standard definition of a glass (or vitreous solid) is a solid formed by rapid melt quenching. The term glass is often used to describe any amorphous solid that exhibits a glass transition temperature Tg. If the cooling is sufficiently rapid (relative to the characteristic crystallization t...
572982021d046914007794f1
What must happen quickly for glass to form?
cooling
[ "Glass\n\nIn physics, the standard definition of a glass (or vitreous solid) is a solid formed by rapid melt quenching. The term glass is often used to describe any amorphous solid that exhibits a glass transition temperature Tg. If the cooling is sufficiently rapid (relative to the characteristic crystallization t...
572982021d046914007794f2
What predicts glass-forming ability?
rigidity theory
[ "Glass\n\nIn physics, the standard definition of a glass (or vitreous solid) is a solid formed by rapid melt quenching. The term glass is often used to describe any amorphous solid that exhibits a glass transition temperature Tg. If the cooling is sufficiently rapid (relative to the characteristic crystallization t...
572984596aef051400154f9c
What does glass not have, leading some to think it is a liquid?
first-order phase transition
[ "Glass\n\nSome people consider glass to be a liquid due to its lack of a first-order phase transition where certain thermodynamic variables such as volume, entropy and enthalpy are discontinuous through the glass transition range. The glass transition may be described as analogous to a second-order phase transition...
572984596aef051400154f9d
What theory isn't completely valid for glass?
equilibrium theory of phase transformations
[ "Glass\n\nSome people consider glass to be a liquid due to its lack of a first-order phase transition where certain thermodynamic variables such as volume, entropy and enthalpy are discontinuous through the glass transition range. The glass transition may be described as analogous to a second-order phase transition...
572984596aef051400154f9e
Transition in glass is comparable to what?
a second-order phase transition
[ "Glass\n\nSome people consider glass to be a liquid due to its lack of a first-order phase transition where certain thermodynamic variables such as volume, entropy and enthalpy are discontinuous through the glass transition range. The glass transition may be described as analogous to a second-order phase transition...
572988531d04691400779513
Atomically, glass is similar to what?
a supercooled liquid
[ "Glass\n\nAlthough the atomic structure of glass shares characteristics of the structure in a supercooled liquid, glass tends to behave as a solid below its glass transition temperature. A supercooled liquid behaves as a liquid, but it is below the freezing point of the material, and in some cases will crystallize ...
572988531d04691400779514
What acts like a liquid but is under the freezing temperature?
A supercooled liquid
[ "Glass\n\nAlthough the atomic structure of glass shares characteristics of the structure in a supercooled liquid, glass tends to behave as a solid below its glass transition temperature. A supercooled liquid behaves as a liquid, but it is below the freezing point of the material, and in some cases will crystallize ...
572988531d04691400779515
Despite its atomic structure, cooled glass acts like what?
a solid
[ "Glass\n\nAlthough the atomic structure of glass shares characteristics of the structure in a supercooled liquid, glass tends to behave as a solid below its glass transition temperature. A supercooled liquid behaves as a liquid, but it is below the freezing point of the material, and in some cases will crystallize ...
572988531d04691400779516
In cooled glass, what types of movement stop?
rotational and translational
[ "Glass\n\nAlthough the atomic structure of glass shares characteristics of the structure in a supercooled liquid, glass tends to behave as a solid below its glass transition temperature. A supercooled liquid behaves as a liquid, but it is below the freezing point of the material, and in some cases will crystallize ...
57291ce0af94a219006aa089
What is energy abbreviated to in science?
E
[ "Planck_constant\n\nFirst recognized in 1900 by Max Planck, it was originally the proportionality constant between the minimal increment of energy, E, of a hypothetical electrically charged oscillator in a cavity that contained black body radiation, and the frequency, f, of its associated electromagnetic wave. In 1...
57291ce0af94a219006aa08a
What is frequency also known as in science?
f
[ "Planck_constant\n\nFirst recognized in 1900 by Max Planck, it was originally the proportionality constant between the minimal increment of energy, E, of a hypothetical electrically charged oscillator in a cavity that contained black body radiation, and the frequency, f, of its associated electromagnetic wave. In 1...
57291ce0af94a219006aa08b
What term describes a small amount of element?
quantum
[ "Planck_constant\n\nFirst recognized in 1900 by Max Planck, it was originally the proportionality constant between the minimal increment of energy, E, of a hypothetical electrically charged oscillator in a cavity that contained black body radiation, and the frequency, f, of its associated electromagnetic wave. In 1...
57291ce0af94a219006aa08c
What did the light quantum, in some ways, behave as?
an electrically neutral particle
[ "Planck_constant\n\nFirst recognized in 1900 by Max Planck, it was originally the proportionality constant between the minimal increment of energy, E, of a hypothetical electrically charged oscillator in a cavity that contained black body radiation, and the frequency, f, of its associated electromagnetic wave. In 1...
57291ce0af94a219006aa08d
What was later termed the photon?
The light quantum
[ "Planck_constant\n\nFirst recognized in 1900 by Max Planck, it was originally the proportionality constant between the minimal increment of energy, E, of a hypothetical electrically charged oscillator in a cavity that contained black body radiation, and the frequency, f, of its associated electromagnetic wave. In 1...
57295e056aef051400154d84
When did Max Planck first recognize the value of the Planck constant?
1900
[ "Planck_constant\n\nFirst recognized in 1900 by Max Planck, it was originally the proportionality constant between the minimal increment of energy, E, of a hypothetical electrically charged oscillator in a cavity that contained black body radiation, and the frequency, f, of its associated electromagnetic wave. In 1...
57295e056aef051400154d85
Which scientist associated the Planck constant with a quantum five years after Planck's recognition?
Einstein
[ "Planck_constant\n\nFirst recognized in 1900 by Max Planck, it was originally the proportionality constant between the minimal increment of energy, E, of a hypothetical electrically charged oscillator in a cavity that contained black body radiation, and the frequency, f, of its associated electromagnetic wave. In 1...