A factory in Indonesia produces cement by heating limestone with clay in a rotary kiln. Which compound is the main calcium-containing product formed when limestone is heated in this process?

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Question

A factory in Indonesia produces cement by heating limestone with clay in a rotary kiln. Which compound is the main calcium-containing product formed when limestone is heated in this process?

Accepted Answer

calcium oxide — Award 1 mark for identifying calcium oxide (CaO) as the product of thermal decomposition of limestone (calcium carbonate). A is incorrect — calcium hydroxide is formed when calcium oxide reacts with water. B is incorrect — calcium carbonate is the reactant, not the product. D is incorrect — calcium hydrogencarbonate is formed in solution when excess CO₂ reacts with calcium carbonate.

Answer

calcium oxide

Answer

calcium carbonate

Answer

calcium hydroxide

Answer

calcium hydrogencarbonate

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