Which will have greater volume when the following gases are compared at STP : 1.25L `O_2` at STP

Explanation

To determine which gas has a greater volume at Standard Temperature and Pressure (STP), we can use the Ideal Gas Law and the concept of molar volume. At STP, one mole of any ideal gas occupies 22.4 liters.

### Step-by-Step Solution:

1. **Identify the Given Information:**
- Volume of `O2` (oxygen) = 1.25 L
- STP conditions: Pressure = 760 mm Hg, Temperature = 273 K

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