When 4.54 g of a nonelectrolyte solute is dissolved in 565 mL of water at 29 °C, the resulting solution exerts an osmotic pressure of 835 torr.

What is the molar concentration of the solution?
How many moles of solute are in the solution?
What is the molar mass of the solute?

1 answer

pi = MRT
Use pi in atm and T in kelvin. R is 0.08206. Solve for M = molarity.
mols = M x L = ?
Then n = grams/molar mass. You know mols and grams, solve for molar mass.