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Glass and clay ceramics

Glass ceramics

Glass is and but it is .

Glass shatters when it is hit or dropped
Image caption,
Glass shatters when it is hit or dropped

Most of the glass we use is soda-lime glass. This is made by melting a mixture of sand (silicon oxide), sodium carbonate and limestone, then allowing the liquid to cool and solidify.

Borosilicate glass is made by heating sand with boron trioxide. Borosilicate glass has a much higher melting point than soda-lime glass.

Question

State and explain which type of glass would be best to make a boiling tube, for use in a school chemistry laboratory.

Clay ceramics

Clay ceramics include brick, china and porcelain. They are made by shaping wet clay and then heating it to a high temperature in a furnace, which causes to form and join together.

Clay ceramics are often coated with a glaze, which hardens on heating to form a hard, smooth, and waterproof layer. This explains why they are often used for dinner plates and bowls.

Brick is strong in compression - it resists being squashed
Image caption,
Brick is strong in compression - it resists being squashed