Hey Lola, if there was a 6 mark question on limestone it would most likely be asking what the cycle is and the uses for each product on the cycle and it may possibly ask for the chemical symbols for each.
The main points to answer this with would be: - Calcium carbonate (CaCo3) is used for building materials (Mortar, cement, concrete, and glass) - Calcium carbonate decomposes when heated producing CO2 and Calcium oxide (CaO) - Calcium oxide can be used to neutralise acid soils and lakes - Calcium oxide is added to a small amount of water to make Calcium hydroxide in a solid state (Ca(OH)2) - Calcium Hydroxide is also used for neutralising acid soils - When calcium hydroxide is mixed with more water, it produces calcium hydroxide but in an aqueous state (Dissolved in water) (Ca(OH)2) - Calcium hydroxide in aqueous state is used for testing for CO2 (It goes cloudy)
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