State one relevant observation for each of the following reactions :
Copper carbonate is decomposed on heating.

Explanation

To answer the question regarding the decomposition of copper carbonate upon heating, we can break down the solution into clear steps:

### Step-by-Step Solution:

1. **Identify the Reactant**: The reactant in this reaction is copper carbonate, which has the chemical formula CuCO₃.

2. **Observation of Color**: Before heating, copper carbonate is typically green in color. This is an important observation to note.

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