Chem math problems please help me if you can?

1) The vapor pressure of a solution containing 53.6 g glycerin (C3H8O3) in 133.7 g ethanol (C2H5OH) is 133 torr at 40 degree C. Calcutale the vapor pressure of pure ethanol at 40 degree C. assuming that glycerin is a nonvolatile, nonelectrolyte solute in ethanol.

2) A solution of sodium chloride in water has a vapor pressure of 19.6 torr at 25degree C. What is the mole fraction of NaCl solute particles in this solution. What would be the vapor pressure of this solution at 45 degree C. ? The vapor pressure of pure water is 23.8 torr at 25 degree C. and 71.9 torr at 45 degree C and assume sodium chloride exists as Na and Cl ions in solution

Answer:
1) We use Raoult's law that states
P(A )= P°(A) XA
XA is the Mole fraction

molar mass glycerin = 92 g/mol
moles glycerin = 53.6 g / 92 = 0.583

molar mass ethanol = 46 g/mol
moles ethanol = 133.7 / 46 = 2.91

XA = 2.91 / 2.91 + 0.583 = 0.833

133 = P°(A) x 0.833
P°(A) = 133 / 0.833 = 159.7 torr

2)
19.6 = 23.8 X(A)
X(A) = 19.6 / 23.8 = 0.823

P (A) = 71.9 x 0.823 = 59.2 torr at 45°C

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Chem math problems please help me if you can?

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