Posted by Tsomo on .
When 3.15 g of a nonelectrolyte solute is dissolved in water to make 135 mL of solution at 21 °C, the solution exerts an osmotic pressure of 869 torr.
What is the molar mass of the solute?
What is the molar concentration of the solution?
How many moles of solute are in the solution?

Chemistry 
DrBob222,
pi = MRT
pi = 869/760 = ?
M solve for this
R = 0.08205 L*atm/mol*k
T = 273 + 21 = ?
M gives you part b.
Then M = mols/L solution, you know L solution and M, solve for mols and that is part c.
Part a is mol = grams/molar mass. You know grams and mols, solve for molar mass.