What is the number of moles of solute in a 500.0 mL solution that has an osmotic pressure of 2.50 atm at 25°C?
Correct: B
To calculate the number of moles of solute, we can use the equation π = cRT, where π is the osmotic pressure, c is the concentration of the solution, R is the gas constant, and T is the temperature in Kelvin. Rearranging the equation to solve for c, we get c = π / RT = 2.50 atm / (0.0821 L*atm/mol*K * 298 K) = 0.102 M. Then, we can calculate the number of moles: moles = M * V = 0.102 M * 0.500 L = 0.051 mol, which is closest to 0.05 mol or 0.05 * 2 = 0.10 mol when doubling the volume to match the given choices.