The primary component of glass is silica (silicon dioxide, SiO₂), which is typically derived from sand.
How are the silicon and oxygen atoms arranged in glass?
The silicon and oxygen atoms are arranged in a continuous random network.
How is glass typically made?
Glass is made by melting a mixture of materials and rapidly cooling it to prevent crystallization.
What is fused silica glass mainly composed of?
Fused silica glass consists almost entirely of silicon dioxide (SiO₂).
Why is fused silica glass highly resistant to thermal shock?
It has a very high melting point and does not easily change shape when heated.
Which type of glass is most commonly used in everyday applications like bottles and jars?
Soda-lime glass is commonly used in everyday glassware such as bottles and jars.
What are the main components of soda-lime glass?
Soda-lime glass consists of silicon dioxide (SiO₂), sodium carbonate (Na₂CO₃), and calcium carbonate (CaCO₃).
Why is soda-lime glass not resistant to thermal shock?
It has a lower melting point and lacks the thermal expansion properties of borosilicate glass.
What is borosilicate glass used for?
Borosilicate glass is used in laboratory glassware, ovenware, cookware (such as Pyrex), car headlights, and streetlights.
What special element in borosilicate glass helps resist thermal shock?
Boron trioxide (B₂O₃) reduces thermal expansion, making borosilicate glass resistant to thermal shock.
Which type of glass has a high refractive index, making it sparkle?
Lead crystal glass has a high refractive index, giving it a sparkling appearance.
Why is lead crystal glass heavier than other glass types?
Lead crystal glass contains lead(II) oxide (PbO), which increases its density.
Which type of glass darkens when exposed to ultraviolet (UV) light?
Photochromic glass darkens when exposed to UV light and becomes transparent again in its absence.
What chemicals are added to make photochromic glass?
Silver chloride (AgCl) and copper(I) chloride (CuCl) are added to make photochromic glass.
Why is Indium Tin Oxide (ITO) glass special?
Indium Tin Oxide (ITO) glass is both transparent and electrically conductive.
What is ITO glass mainly used for?
ITO glass is used in LCD screens, panel displays, and touchscreens.
Why is glass considered chemically inert?
Glass does not react easily with most chemicals, making it suitable for storing food and laboratory chemicals.
What property of glass makes it useful for optical instruments and windows?
Transparency allows light to pass through glass, making it ideal for optical instruments and windows.
Why is glass brittle?
Glass has a rigid atomic structure that lacks flexibility, making it brittle and prone to shattering under stress.
What is the main difference between fused silica glass and soda-lime glass?
Fused silica glass consists almost entirely of silicon dioxide (SiO₂) and has a high melting point, whereas soda-lime glass contains additional compounds like sodium carbonate (Na₂CO₃) and calcium carbonate (CaCO₃), making it easier to shape but less resistant to heat.
Explanation Questions
Why does glass not have a crystalline structure?
Glass cools rapidly from its molten state, preventing the formation of a regular crystalline structure, resulting in an amorphous solid.
How does adding lead(II) oxide (PbO) to glass affect its properties?
Adding lead(II) oxide increases the refractive index, making the glass sparkle more, and also makes it denser and easier to cut.
Why is borosilicate glass used in laboratory and kitchenware?
Borosilicate glass is resistant to thermal shock and chemical corrosion, making it suitable for laboratory and kitchen use.
Explain how photochromic glass darkens in sunlight.
Photochromic glass contains silver chloride (AgCl), which undergoes a chemical reaction when exposed to UV light, darkening the glass.
Why is soda-lime glass preferred for making bottles and containers?
Soda-lime glass is affordable, easy to mold, and recyclable, making it ideal for mass production of bottles and containers.
Why does fused silica glass have a higher melting point than other types of glass?
Fused silica glass is almost pure silicon dioxide (SiO₂), which has strong covalent bonds requiring high temperatures to break.
Explain why Indium Tin Oxide (ITO) glass is used in touchscreens.
ITO glass is transparent and electrically conductive, allowing it to function as a responsive surface in touchscreens.
Why does glass shatter when subjected to high stress?
Glass lacks flexibility and has an atomic structure that does not absorb stress, causing it to fracture under pressure.
Why is chemical resistance an important property of glass?
Chemical resistance allows glass to store corrosive substances without reacting, making it ideal for laboratory and food storage.
How does the composition of glass affect its properties?
The composition of glass determines its hardness, transparency, resistance to heat, and brittleness. For example, adding boron trioxide (B₂O₃) to borosilicate glass reduces thermal expansion, while adding lead(II) oxide (PbO) to lead crystal glass increases its refractive index, making it sparkle.