A first order reaction is 20% complete in 10 min. What is the rate constant?

Explanation

To find the rate constant \( k \) for a first-order reaction that is 20% complete in 10 minutes, we can follow these steps:

### Step 1: Understand the reaction completion
Since the reaction is 20% complete, it means that 80% of the reactant remains. If we denote the initial concentration of the reactant as \( [A_0] \), then after 10 minutes, the concentration \( [A] \) can be expressed as:
\[ [A] = [A_0] \times (1 - 0.20) = [A_0] \times 0.80 \]

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