How many times the rate of reaction will change if temperature is increased from `20^(@)C` to `50^(@)C` ?

Explanation

To determine how many times the rate of reaction will change when the temperature is increased from \(20^\circ C\) to \(50^\circ C\), we can use the general rule of thumb in chemical kinetics, which states that for many reactions, the rate of reaction approximately doubles with every \(10^\circ C\) increase in temperature.

### Step-by-Step Solution:

1. **Identify the Initial and Final Temperatures**:
- Initial Temperature, \(T_1 = 20^\circ C\)
- Final Temperature, \(T_2 = 50^\circ C\)

2. **Calculate the Temperature Increase**:
- The increase in temperature, \(\Delta T = T_2 - T_1 = 50^\circ C - 20^\circ C = 30^\circ C\)

3. **Determine the Number of \(10^\circ C\) Increments**:
- Since the temperature is increased by \(30^\circ C\), we can divide this by \(10^\circ C\):
\[ \text{Number of increments} = \frac{30^\circ C}{10^\circ C} = 3 \]

4. **Apply the Doubling Rule**:
- According to the rule, the rate of reaction doubles with each \(10^\circ C\) increase. Therefore, after three \(10^\circ C\) increments, the rate will change as follows:
\[ \text{Rate Change} = 2^n = 2^3 = 8 \]

5. **Conclusion**:
- Thus, the rate of reaction will increase by a factor of \(8\) when the temperature is increased from \(20^\circ C\) to \(50^\circ C\).

### Final Answer:
The rate of reaction will change by a factor of \(8\).