A 150.0 mL sample of an aqueous solution at 25°C contains 15.2 mg of an unknown nonelectrolyte compound.If the solution has an osmotic pressure of 8.44 torr,what is the molar mass of the unknown compound?
A) 223 g/mol
B) 294 g/mol
C) 341 g/mol
D) 448 g/mol
E) 195 g/mol

Question

Quizplus · Accepted Answer

The correct answer is A because the molar mass of the unknown compound is 223 g/mol. This can be calculated using the formula:Molar mass = (Mass of solute) / (Volume of solution in liters) * (Osmotic pressure in atm)In this case, the mass of solute is 15.2 mg, the volume of solution is 150.0 mL (which is 0.1500 L), and the osmotic pressure is 8.44 torr (which is 0.0111 atm). Plugging these values into the formula, we get:Molar mass = (15.2 mg) / (0.1500 L) * (0.0111 atm) = 223 g/mol

A 1500 ML Sample of an Aqueous Solution at 25°C Contains