Calculate the vapor pressure lowering of water when 5.67 g of glucose, C6H12O6, is dissolved in 25.2 g of water at 25 ºC. The vapor pressure of water at 25º C is 23.8 mmHg. What is the vapor pressure of the solution?

Answer 1

mols glucose = g/molar mass
mols H2O = grams/molar mass

XH2O = n H2O/total mols, then
Psoln = XH2O*P^o_normal

For lowering, use
delta P_solvent =X_solute*P^o_normal

Answer 2

100 gram solution of 10 gram of magnesium.klorida and 90 gram of water what is the vapor pressure lowering of a solution if p h2o=31 mmhg