A gas occupies a volume of 250 ml at 745 mm Hg and `25^∘C`. What additional pressure is required to reduce the gas volume to 200 ml at the same time?

Explanation

To solve the problem of determining the additional pressure required to reduce the volume of a gas from 250 ml to 200 ml at constant temperature, we can use Boyle's Law. Boyle's Law states that for a given mass of gas at constant temperature, the product of pressure and volume is constant.

### Step-by-Step Solution:

1. **Identify the Given Values**:
- Initial Pressure (P1) = 745 mm Hg
- Initial Volume (V1) = 250 ml
- Final Volume (V2) = 200 ml
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