Question

A flask contains equal masses of f2 and cl2 with a total pressure of 2.00 atm at 298k. What is the partial pressure of cl2 in the flask?

Answer 1

Answer:

Partial Pressure of F₂ = 1.30 atm

Partial pressure of Cl₂ = 0.70 atm

Explanation:

Partial pressure for gases are given by Daltons law.

Total pressure of a gas mixture = sum of the partial pressures of individual gases

Pt = P(f₂) + P(cl₂)

Partial pressure = mole fraction × total pressure

Let the mass of each gas present be m

Number of moles of F₂ = m/38 (molar mass of fluorine = 38 g/Lol

Number of moles of Cl₂ = m/71 (molar mass of Cl₂)

Mole fraction of F₂ = (m/38)/((m/38) + (m/71)) = 0.65

Mole fraction of Cl₂ = (m/71)/((m/38) + (m/71)) = 0.35 or just 1 - 0.65 = 0.35

Partial Pressure of F₂ = 0.65 × 2 = 1.30 atm

Partial pressure of Cl₂ = 0.35 × 2 = 0.70 atm