C1 2.3 The Limestone Reaction Cycle.

Front 1

Give an example of a use of Calcium Hydroxide.

Back 1

-Calcium hydroxide is soluble in water and forms a solution, limewater, used to test for carbon dioxide.
-Calcium oxide, calcium hydroxide and calcium carbonate can be used to neutralise soil acidity.
-Calcium carbonate can be used to remove acidic gases from coal-fired power station chimneys reducing harmful emissions and acid rain.

Front 2

Write the word equation of the reaction of the Limestone reaction cycle:

Back 2

Calcium carbonate is heated and decomposes, forming calcium oxide (lime) and releasing carbon dioxide gas.
Calcium carbonate ---> calcium oxide + carbon dioxide

When water is added to calcium oxide heat is generated, steam is released, and forms slaked lime (calcium hydroxide).
Calcium oxide + water ---> calcium hydroxide

Calcium carbonate reacts with acids to release carbon dioxide gas.
Calcium carbonate + hydrochloric acid ---> calcium chloride + carbon dioxide

Front 3

Explain why farmers may choose to use calcium hydroxide in their fields.

Back 3

To neutralise the acidity levels in the soil from which the farmers grow their crops.