A 376 mg sample of a nonelectrolyte compound isolated from throat lozenges was dissolved in water to produce 10.0 mL of a solution at 25 $\circ$ C.The osmotic pressure of this solution was measured and found to be 4.89 atm.What is the molar mass of this compound?

Question

Quizplus · Accepted Answer

The correct answer is A because the osmotic pressure is given by the equation:π = MRTwhere π is the osmotic pressure, M is the molarity of the solution, R is the ideal gas constant, and T is the temperature in Kelvin.We can rearrange this equation to solve for the molarity of the solution:M = π / RTSubstituting the given values into this equation, we get:M = 4.89 atm / (0.0821 L atm / (mol K) * 298 K) = 0.200 MThe molarity of the solution is 0.200 M, which means that there are 0.200 moles of the compound in 10.0 mL of solution.We can use the mass of the compound and the volume of the solution to calculate the molar mass of the compound:Molar mass = mass / molesSubstituting the given values into this equation, we get:Molar mass = 376 mg / 0.200 moles = 188 g/molTherefore, the molar mass of the compound is 188 g/mol.

A 376 Mg Sample of a Nonelectrolyte Compound Isolated from Throat