We can solve this problem using the ideal gas law and the mole fraction concept. Here are the steps:

Step 1: Use the Ideal Gas Law to find the total moles of gas.

The ideal gas law equation is:

$PV = nRT$

Where:

• $P$ is the total pressure (1.02 atm),
• $V$ is the volume of the container (0.75 L),
• $n$ is the total moles of gas,
• $R$ is the ideal gas constant ($0.0821 \, \text{L·atm/(mol·K)}$),
• $T$ is the temperature in Kelvin (273 K).

We can rearrange this equation to solve for $n$:

$n = \frac{PV}{RT}$

Substituting the values:

$n = \frac{(1.02) \times (0.75)}{(0.0821) \times (273)}$

Let’s calculate the value of $n$.