In a gaseous reaction `A to B + C `, the pressure of A falls from 0.2 atm to 0.15 atm in one hour. Calculate the rate constant if it is a first-order reaction. What will be the pressure of A after 1.5 hours?

Explanation

To solve the problem, we need to calculate the rate constant \( k \) for the first-order reaction and then determine the pressure of \( A \) after 1.5 hours. Let's break it down step by step.

### Step 1: Identify the initial and final pressures
- Initial pressure of \( A \) (\( P_0 \)) = 0.2 atm
- Final pressure of \( A \) after 1 hour (\( P_t \)) = 0.15 atm

### Step 2: Calculate the change in pressure
- Change in pressure (\( x \)) = \( P_0 - P_t = 0.2 \, \text{atm} - 0.15 \, \text{atm} = 0.05 \, \text{atm} \)
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