When lead nitrate is heated it breaks down into lead monoxide, nitrogen dioxide and oxygen
`2Pb(NO_(3))_(2) to 2PbO + 4NO_(2) + O_(2)`
The reaction is an example of

Options

A. combination reaction
B. decomposition reaction
C. double decomposition reaction
D. displacement reaction

Explanation

To solve the question regarding the decomposition of lead nitrate when heated, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reaction**: The reaction given is:
\[ 2Pb(NO_3)_2 \rightarrow 2PbO + 4NO_2 + O_2 \]
This shows that lead nitrate decomposes into lead monoxide, nitrogen dioxide, and oxygen upon heating.

2. **Understand the Type of Reaction**: We need to classify the type of chemical reaction that is occurring.

3. **Definition of Decomposition Reaction**: A decomposition reaction is defined as a reaction where one reactant breaks down into two or more products. In this case, lead nitrate (the reactant) is breaking down into lead monoxide, nitrogen dioxide, and oxygen (the products).

4. **Eliminate Other Reaction Types**:
- **Combination Reaction**: This type involves two or more reactants combining to form a single product. This does not apply here, as we have one reactant breaking down.
- **Displacement Reaction**: This involves one element displacing another in a compound. There is no displacement occurring in this reaction.
- **Double Decomposition Reaction**: This involves two compounds reacting to form two new compounds. This does not apply either, as we only have one reactant.

5. **Conclusion**: Since the reaction involves the breakdown of a single reactant into multiple products, it is classified as a **decomposition reaction**.

### Final Answer:
The reaction is an example of a **decomposition reaction**.

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