In a mixture of CH4 and Cl2 gases, the partial pressure of CH4 is 0.145 atm. HELP!!?

Question

In a mixture of CH4 and Cl2 gases, the partial pressure of CH4 is 0.145 atm. The total pressure is 0.445 atm. The temperature is 28.0oC. If the total volume of the gas mixture is 403 mL, what is the mass of Cl2 in grams?

how do i get it? step by step

Answer 1

First, you find the pressure of Cl2. Then you use PV=nRT to find the moles of Cl2. Then you convert moles of Cl2 into the mass of Cl2

The total pressure is the sum of the partial pressures.

Total pressure = Pressure of CH4 + Pressure of Cl2

Pressure of Cl2 = Total pressure - Pressure CH4

Pressure of Cl2 = 0.445 - 0.145 = 0.300 atm

Now just use the formula PV=nRT to find the moles of Cl2:

PV = nRT

n = PV/RT

n = (0.300)(.403)/(0.0821)(301)

n = 4.89 x 10^(-3) moles of Cl2

Mass of Cl2 = moles of Cl2 * molar mass of Cl2

Mass of Cl2 = (4.89 x 10^-3) * (2*35.45)

*** Mass of Cl2 = 0.35 g