6.00 g of hemoglobin was dissolved in 250.0 mL of solution. The resulting osmotic pressure was 6.80 mmHg at 23.0C. what is the molar mass of hemoglobin?

Answer 1

Convert 6.80 mm Hg to atmospheres. 6.80/760 = ? = pi (not 3.14 but pi in this case is osmotic pressure).
pi = MRT
pi from above.
You know R and T (remember T must be in kelvin).
Solve for M = molarity = mols/L
You know M and L, solve for mols.
Then mols = grams/molar mass. You know mols and grams, solve for molar mass.

Post your work if you get stuck.

Answer 2

got it! thanks so much