Which is the correct pair of solid residue and gas in decomposition of calcium carbonate?
Answer and explanation
Correct answer: Calcium oxide and carbon dioxide
The thermal decomposition equation is CaCO₃(s) → CaO(s) + CO₂(g). Calcium oxide remains behind as the solid residue, while carbon dioxide escapes as a gas. The products are determined by the composition of the carbonate: the calcium forms the oxide and the carbonate part releases carbon dioxide. Hydroxide, sulphate, chloride, hydrogen, oxygen, and nitrogen are not products of this reaction.
Frequently asked questions
What is the correct answer to this question?
Calcium oxide and carbon dioxide
Why is this the correct answer?
The thermal decomposition equation is CaCO₃(s) → CaO(s) + CO₂(g). Calcium oxide remains behind as the solid residue, while carbon dioxide escapes as a gas. The products are determined by the composition of the carbonate: the calcium forms the oxide and the carbonate part releases carbon dioxide. Hydroxide, sulphate, chloride, hydrogen, oxygen, and nitrogen are not products of this reaction.
Which subject and chapter does this question cover?
This is a Class 10 Science question. Chapter: Chemical Substances – Nature and Behaviour. Topic: Chemical Reactions and Equations.
