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Using materials - AQAGlass and clay ceramics

Metals have many properties but some are prone to corrosion. Alloying metals improve their properties. Ceramics, polymers and composites have desirable properties that allows them specific uses.

Part of Chemistry (Single Science)Using resources

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