1216 mmHg = Partial pressure N₂
Explanation:
In a mixture of n gases, the partial pressure of each compound follows the equation:
Total pressure = Partial pressure n₁ + Partial pressure n₂ + Partial pressure n₃ + Partial pressure n₄ + Partial pressure n₅ + ... + Partial pressure nₙ
In a mixture of O₂, He and N₂, the total pressure = 3040mmHg is defined as:
3040 mmHg = Partial pressure O₂ + Partial pressure He + Partial pressure N₂
Replacing:
3040 mmHg = 304 mmHg + 1520 mmHg + Partial pressure N₂
3040 mmHg = 1824 mmHg + Partial pressure N₂
1216 mmHg = Partial pressure N₂