10% of a reactant decomposes in 1 hour, 20% in 2 hours and 30% in 3 hours. The order of the reaction is

Options

A. 0
B. 1
C. 2
D. 3

Answer

To determine the order of the reaction based on the given data, we can analyze the percentage decomposition of the reactant over time.

### Step-by-Step Solution:

1. **Understanding the Data**:
- In 1 hour, 10% of the reactant decomposes.
- In 2 hours, an additional 10% decomposes (total 20%).
- In 3 hours, an additional 10% decomposes (total 30%).

2. **Percentage Decomposition Analysis**:
- From 0 to 1 hour: 10% decomposed.
- From 1 to 2 hours: 10% decomposed (total 20%).
- From 2 to 3 hours: 10% decomposed (total 30%).

3. **Identifying the Pattern**:
- The amount of reactant decomposed in each hour is constant (10%).
- This indicates that the rate of reaction is independent of the concentration of the reactant.

4. **Determining the Order of Reaction**:
- For a zero-order reaction, the rate of reaction is constant and does not depend on the concentration of the reactant.
- Since the same amount of reactant is decomposed in each time interval (10% per hour), this suggests that the reaction follows zero-order kinetics.

5. **Conclusion**:
- Based on the analysis, we conclude that the order of the reaction is **zero-order**.