Mole percent of O2 = 10% = 0.1 moles
Mole percent of N2 = 10% = 0.1 moles
Mole percent of He = 80% = 0.8 moles
Molar Mass of O2 = (2 x 16) x 0.1 = 3.2
Molar Mass of N2 = (2 x 14) x 0.1 = 2.8
Molar Mass of He = 4 x 0.8 = 3.2
1. Molar Mass of the mixture = 3.2 + 2.8 + 3.2 = 9.2 grams
2. Since at constant volume density is proportional to mass, so the ratio of
mass will be the ratio of density.
Ratio = Molar Mass of the mixture / Molar Mass of O2 = 9.2 / 32 = 0.2875
Answer : The vapor pressure of solution is 23.67 mmHg.
Solution:
As the relative lowering of vapor pressure is directly proportional to the amount of dissolved solute.
The formula for relative lowering of vapor pressure will be,
where,
= vapor pressure of pure solvent (water) = 23.76 mmHg
= vapor pressure of solution= ?
= mass of solute (sucrose) = 12.25 g
= mass of solvent (water) = 176.3 g
= molar mass of solvent (water) = 18.02 g/mole
= molar mass of solute (sucrose) = 342.3 g/mole
Now put all the given values in this formula ,we get the vapor pressure of the solution.
Therefore, the vapor pressure of solution is 23.67 mmHg.
D. The kilogram is a unit of mass.
Your answer should be heat energy!
