Chemistry unit 1: using limestone (all of the build ups and break downs of limestone)

Limestone is mainly calcium carbonate - CaCO3

2) When it's heated it thermally decomposes to make Calcium Oxide and Carbn Dioxide.

CALCIUM CARBONATE - CALCIUM OXIDE + CARBON DIOXIDE

When Magnesium, Copper, ZInc and sodium Carbonates are heated they decompose in the same way.

Calcium carbonate reacts with acid to make a calcium salt, carbon dioxide and water.

1) CALCIUM CARBONATE + SULPHURIC ACID - CALCIUM SULPHATE + CARBON DIOXIDE + WATER.

The type of salt produced depends on the type of acid. For example, a reaction with Hydrochloric acid would make a chloride.

Other Carbonates that react with acids are magnesium, copper, zinc and sodium.

When you add water to calcium oxide you get calcium hydroxide.

CALCIUM OXIDE + WATER - CALCIUM HYDROXIDE

1) Calcium hydroxide is an alkali which can be used to neutralise acidic soil in fields.

2) When Calcium hydroxide is mixed with water it makes a solution called limewater.
Limewater can be used as a test for Carbon Dioxide. If you bubble gas through it, the solution will turn cloudy if the gas is carbon dioxide. This is the reaction:

CALCIUM HYDROXIDE + CARBON DIOXIDE - CALCIUM CARBONATE + WATER.

1) Limestone can be heated with clay to make cement.
2) Cement can be mixed with sand and water to make mortar.
3) Or you can mix cement with sand and aggregate to make concrete.