The pressure in a bulb dropped from `2000` to `1500 mm Hg` in `47 min` when the contained oxygen leaked through a small hole. The bulb was then evacuated. A mixture of oxygen and another gas of molecular weight `79` in the molar ratio of `1:1` at a total pressure of `4000 mm` of mercury was introduced. Find the molar ratio of the two gases remaining in the bulb after a period of `74 min`.

Explanation

To solve the problem step by step, we will follow the reasoning laid out in the video transcript while ensuring clarity in each step.

### Step 1: Understand the Initial Conditions
The pressure in the bulb initially drops from 2000 mm Hg to 1500 mm Hg in 47 minutes due to the leakage of oxygen. This means that the change in pressure is:
\[ \Delta P = 2000 \, \text{mm Hg} - 1500 \, \text{mm Hg} = 500 \, \text{mm Hg} \]

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