On heating blue coloured powder of copper (II) nitrate in a boiling tube, copper oxide (black), oxygen gas and a brown gas X is formed.
Identity the type of reaction.

Explanation

To determine the type of reaction that occurs when heating copper (II) nitrate, we can follow these steps:

### Step 1: Identify the Reactant
The reactant in this reaction is copper (II) nitrate, which has the chemical formula Cu(NO₃)₂. It is a blue-colored powder.

**Hint:** Look for the chemical formula of the reactant to understand its composition.

### Step 2: Describe the Reaction Conditions
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