The concentration of reaction decreases from 0.2 M to 0.05 M in 5 minutes. The rate of reaction in mole. `"lit"^(-1)."sec"^(-1)` is

Options

A. `8.3 xx 10^(-4)`
B. 0.05
C. 0.0005
D. 0.15

Explanation

To find the rate of reaction based on the given concentration change, we can follow these steps:

### Step 1: Determine the change in concentration
The concentration decreases from 0.2 M to 0.05 M.

\[ \text{Change in concentration} = \text{Initial concentration} - \text{Final concentration} = 0.2 \, \text{M} - 0.05 \, \text{M} = 0.15 \, \text{M} \]

### Step 2: Convert time from minutes to seconds
The time given is 5 minutes. We need to convert this into seconds since the rate is required in terms of seconds.

\[ \text{Time in seconds} = 5 \, \text{minutes} \times 60 \, \text{seconds/minute} = 300 \, \text{seconds} \]

### Step 3: Calculate the rate of reaction
The rate of reaction can be calculated using the formula:

\[ \text{Rate} = \frac{\text{Change in concentration}}{\text{Time interval}} = \frac{0.15 \, \text{M}}{300 \, \text{seconds}} \]

### Step 4: Perform the calculation
Now we can perform the calculation:

\[ \text{Rate} = \frac{0.15}{300} = 0.0005 \, \text{mol} \cdot \text{L}^{-1} \cdot \text{s}^{-1} \]

### Final Answer
The rate of reaction is:

\[ \text{Rate} = 0.0005 \, \text{mol} \cdot \text{L}^{-1} \cdot \text{s}^{-1} \]

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