50 g of dinotrogen `(N_(2))` and 2.0 g of helium are enclosed in a vessel already containing 2.0 g of oxygen. Calculated the total pressure and the fraction of the total pressure exerted by He. The volume of the vessel is `10 cm^(3)` and the temperature is 300 K

Explanation

To solve the given problem, we will follow these steps:

### Step 1: Calculate the number of moles of each gas
1. **Dinitrogen (N₂)**:
- Given mass = 50 g
- Molar mass of N₂ = 28 g/mol
- Moles of N₂ = mass / molar mass = 50 g / 28 g/mol = 1.7857 mol

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