Question
Q3) Consider a 10 L container at 0 oC with 40 grams of He and 40 grams of Ar gases:
a) Calculate the partial pressure of Ar in the container?
b) Calculate the partial pressure of He in the container?
c) What is the total pressure of the container?
a) Calculate the partial pressure of Ar in the container?
b) Calculate the partial pressure of He in the container?
c) What is the total pressure of the container?
Answers
DrBob222
Convert 40 g He to moles. moles = grams/molar mass.
Convert 40 g Ar to moles.
Add moles = total n and substitute into PV = nRT and solve for total pressure. That's c.
a and b parts.
Calculate mole fraction He and Ar.
XHe = n He/total moles.
XAr = n Ar/total moles.
PAr = XAr x Ptotal
PHe = XHe x Ptotal.
This can be done another way which may be easier.
moles He = grams/molar mass
moles Ar = grams/molar mass.
Use PV = nRT and substitute n He and solve for PHe.
Use PV = nRT and substitute n Ar and solve for PAr.
Then total P = PHe + P Ar.
Convert 40 g Ar to moles.
Add moles = total n and substitute into PV = nRT and solve for total pressure. That's c.
a and b parts.
Calculate mole fraction He and Ar.
XHe = n He/total moles.
XAr = n Ar/total moles.
PAr = XAr x Ptotal
PHe = XHe x Ptotal.
This can be done another way which may be easier.
moles He = grams/molar mass
moles Ar = grams/molar mass.
Use PV = nRT and substitute n He and solve for PHe.
Use PV = nRT and substitute n Ar and solve for PAr.
Then total P = PHe + P Ar.