Problem 11.115 Bromine is sometimes used as a solution in tetrachloromethane, CC
ID: 525318 • Letter: P
Question
Problem 11.115
Bromine is sometimes used as a solution in tetrachloromethane, CCl4.
Part A
What is the vapor pressure (in mm Hg) of a solution of 6.55 g of Br2 in 107.5 g of CCl4 at 300K? The vapor pressure of pure bromine at 300K is 30.5 kPa, and the vapor pressure of CCl4 is 16.5kPa.
Problem 11.115
Bromine is sometimes used as a solution in tetrachloromethane, CCl4.
Part A
What is the vapor pressure (in mm Hg) of a solution of 6.55 g of Br2 in 107.5 g of CCl4 at 300K? The vapor pressure of pure bromine at 300K is 30.5 kPa, and the vapor pressure of CCl4 is 16.5kPa.
Pvapor=Explanation / Answer
Molar mass of Br2,
MM = 2*MM(Br)
= 2*79.9
= 159.8 g/mol
mass,m = 6.55 g
number of mol of Br2,
n1 = mass/molar mass
= 6.55/159.8
= 0.041 mol
Molar mass of CCl4,
MM = 1*MM(C) + 4*MM(Cl)
= 1*12.01 + 4*35.45
= 153.81 g/mol
mass,m = 107.5 g
number of mol of CCl4,
n2 = mass/molar mass
= 107.5/153.81
= 0.699 mol
total mol = n1 + n2 = 0.041 + 0.699 = 0.740 mol
mole fraction of Br2 = 0.041/0.740 = 0.0554
mole fraction of CCl4 = 1 - 0.0554 = 0.9446
P = po1*X1 + po2*X2
= 30.5*0.0554 + 16.5*0.9446
= 17.3 kPa
Answer: 17.3 kPa
Answer: 17.3 kPa