Question: What property of thorium oxide has caused it to no longer be used in eyeglasses?
Answer: radioactivity

Question: What is another name for lead glass?
Answer: flint glass

Question: What is the benefit of thorium oxide in addition to its refractive index?
Answer: low dispersion

Question: What causes glass to dissolve in water?
Answer: soda

Question: Why is lime often added to glass?
Answer: better chemical durability

Question: What percentage of soda-lime glass is silica?
Answer: 70 to 74

Question: What is a benefit of fused quartz?
Answer: excellent thermal shock characteristics

Question: What besides viscosity is a drawback of fused quartz?
Answer: high melting-temperature

Question: What happens during refining?
Answer: removal of bubbles

Question: What method is used for making windows?
Answer: float glass process

Question: What is used on the surface of window glass to make it smooth?
Answer: nitrogen

Question: What is added to the glass of jars to improve water resistance?
Answer: alumina and calcium oxide

Question: Who were the inventors of the float glass process?
Answer: Alastair Pilkington and Kenneth Bickerstaff

Question: What can be used to make glass less refractive?
Answer: boron

Question: What is the refraction index of typical glass?
Answer: 1.5

Question: What is a toxic additive that increases refraction?
Answer: lead oxide

Question: What are high-index glasses erroneously called?
Answer: crystal

Question: Why are high-index glasses valued?
Answer: for their diamond-like optical properties

Question: Which kinds of glass existed the furthest in the past?
Answer: silicate glasses

Question: What kind of glass are containers made from?
Answer: soda-lime glass

Question: What is sand mostly made of?
Answer: silica

Question: What can a very strong and transparent glass be made from?
Answer: pure silica

Question: What types of glass is the word commonly used to mean?
Answer: silicate glasses

Question: What does glass lack, allowing it to be transparent?
Answer: internal subdivisions

Question: What force gives glass its surface texture?
Answer: surface tension

Question: What, in contrast to glass, doesn't let light pass through?
Answer: polycrystalline materials

Question: What type of glass absorbs some light?
Answer: colored

Question: What kind of glass exists in nature?
Answer: obsidian

Question: Obsidian is what type of glass?
Answer: volcanic

Question: What was obsidian used to make in prehistoric times?
Answer: cutting tools

Question: When are the oldest beads thought to have been made?
Answer: mid third millennium BCE

Question: What glass-like material is made with a method related to glazing?
Answer: faience

Question: What can give glass a faint green tinge?
Answer: iron(II) oxide

Question: What can prevent a green color in glass?
Answer: Manganese dioxide

Question: What other than additives can give glass a yellow color?
Answer: reducing combustion atmosphere

Question: What chemical compounds can make glass nearly black?
Answer: iron polysulfides

Question: Charged ions can be used to produce what in glass?
Answer: Color

Question: What word does "glass" come from?
Answer: glesum

Question: Where did glasswork begin relatively late?
Answer: China

Question: In what year did glassmaking begin in Asia?
Answer: 1730 BCE

Question: What city was a center of glass production for the Romans?
Answer: Trier

Question: In what current country is Trier located?
Answer: Germany

Question: When did stained glass make a big comeback?
Answer: 19th-century

Question: When did stained glass begin to be used for places of worship?
Answer: 10th-century

Question: When did big windows of stained glass become less common?
Answer: the Renaissance

Question: What 13th-century building is an example of stained glass walls?
Answer: Sainte-Chapelle

Question: What did technological changes allow regular homes to have?
Answer: larger windows

Question: What type of glass is used in cars?
Answer: laminated

Question: When did eyeglasses originate?
Answer: late Middle Ages

Question: The walls of skyscrapers are often made of what material?
Answer: glass

Question: What type of power systems use glass?
Answer: solar

Question: What type of scientists rely on glass for distant observations?
Answer: astronomers

Question: What famous lampmaker used glass?
Answer: Louis Comfort Tiffany

Question: When did glassworkers begin to consider their products fine art?
Answer: 1960

Question: What type of glass did many Art Nouveau artists use?
Answer: cameo glass

Question: When did mass production of glass art begin?
Answer: early 20th-century

Question: What early civilization made cameo glass?
Answer: Roman Empire

Question: What makes glass melt at a lower temperature?
Answer: lead(II) oxide

Question: How much less viscous is lead glass compared with soda glass?
Answer: 100 times

Question: Pb2+ causes lead glass to have what?
Answer: high electrical resistance

Question: Lead oxide makes it easier to dissolve what?
Answer: other metal oxides

Question: What components of glass for networks?
Answer: silicon, boron, germanium

Question: What type of components change the network's shape?
Answer: modifiers

Question: What type of component can both make and change networks?
Answer: intermediates

Question: What type of chemical attachment connects ions to the network?
Answer: covalent bond

Question: What component gives glass the ability to conduct electricity?
Answer: alkali metal ions

Question: How can glass be prevented from corroding?
Answer: dealkalization

Question: What types of ions does typical glass have?
Answer: alkali and alkaline earth ions

Question: Reaction with what causes dealkalization?
Answer: sulfur or fluorine compounds

Question: What can alkaline ions in glass harm, in addition to electrical resistance?
Answer: loss tangent

Question: What material is useful in glassmaking because of its slow evaporation?
Answer: sodium selenite

Question: What containers are used for melting?
Answer: platinum crucibles

Question: Why are different materials used in a lab than are used in factory production?
Answer: the cost factor has a low priority

Question: What is the reason for crushing the glass and melting it again?
Answer: homogeneity

Question: Why is glass annealed?
Answer: to prevent breakage

Question: Who coined the term "splat cooling"?
Answer: W. Klement

Question: What are thick alloys made in layers called?
Answer: bulk metallic glasses

Question: What does Liquidmetal Technologies use for their alloys?
Answer: zirconium

Question: What type of metal makes better alloys than traditional steel?
Answer: amorphous steel

Question: At what university was Klement a student?
Answer: Caltech

Question: Who showed that q-glass could be produced from a melt?
Answer: NIST researchers

Question: What shows that there is an inner surface between glass and melt?
Answer: nucleation barrier

Question: What is q-glass?
Answer: an isotropic non-crystalline metallic phase

Question: What kind of microscope shows that q-glass grows as separate particles?
Answer: Transmission electron

Question: What word means that ceramics don't absorb liquids?
Answer: vitreous

Question: What hardens glass-ceramics?
Answer: heat treatment

Question: What materials do glass ceramics have a lot in common with?
Answer: non-crystalline glass and crystalline ceramics

Question: How high of a temperature change can glass-ceramics handle?
Answer: 1000 °C

Question: Because of their heat resistance, glass-ceramics are especially suitable for what?
Answer: countertop cooking

Question: What is the most economically significant property of glass-ceramics?
Answer: impervious to thermal shock

Question: What ingredients give glass-ceramics its useful heat tolerance?
Answer: lithium and aluminosilicates

Question: What proportion of crystalline ceramics yields a product with a CTE of around 0?
Answer: ~70%