Question

How is the partial pressure exerted by n2 gas affected when some o2 is introduced into a container if the temperature and volume remain constant?

Answer 1

Answer:

Addition of O₂ gas does not affect the partial pressure of the N₂ gas, at constant temperature and pressure

Explanation:

Partial pressure (p) of a given gas in a mixture is the pressure exerted by that gas when it occupies the entire volume of container alone.

Whereas, total pressure (P) of the gaseous mixture is given by the Dalton's law and is equal to the sum of partial pressure of individual gas in the mixture, at constant volume and temperature.

Therefore, for a mixture containing N₂ and O₂ gas,

the total pressure (P) = p₁ + p₂

Here, p₁ = partial pressure of N₂

and p₂  = partial pressure of O₂

From this equation it is evident that the partial pressure of each gas is independent of the partial pressure of other gas, at constant volume (V) and temperature (T) and is given by the ideal gas equation:

Partial pressure of N₂ : p₁ = n₁ RT ÷ V

Partial pressure of O₂ : p₂ = n₂ RT ÷ V

Thus, the partial pressure of the N₂ gas (p₁) is dependent on the number of moles of N₂ gas (n₁) only, at constant temperature and pressure.

⇒ p₁ ∝ n₁

Also, the partial pressure of the O₂ gas (p₂) is dependent on the number of moles of O₂ gas (n₂) only, at constant temperature and pressure.

⇒ p₂ ∝ n₂

Therefore, adding O₂ gas does not affect the partial pressure of the N₂ gas, at constant temperature and pressure.