Half life for a first order reaction is 20 minutes . What is its rate constant ?

Explanation

To find the rate constant (k) for a first-order reaction given its half-life (t_half), we can use the formula:

\[ t_{1/2} = \frac{0.693}{k} \]

### Step-by-Step Solution:

1. **Identify the Given Information**:
- The half-life (t_half) of the reaction is given as 20 minutes.
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