If the vapor pressure of pure solvent is 100 mmHg, and the vapor pressure of the
Practice Questions
Q1
If the vapor pressure of pure solvent is 100 mmHg, and the vapor pressure of the solution is 80 mmHg, what is the mole fraction of the solute? (2022)
0.2
0.4
0.5
0.8
Questions & Step-by-Step Solutions
If the vapor pressure of pure solvent is 100 mmHg, and the vapor pressure of the solution is 80 mmHg, what is the mole fraction of the solute? (2022)
Step 1: Understand that the vapor pressure of a pure solvent is given as 100 mmHg.
Step 2: Note that the vapor pressure of the solution is given as 80 mmHg.
Step 3: Recall Raoult's Law, which states that the vapor pressure of the solution (P_solution) is equal to the mole fraction of the solvent (X_solvent) multiplied by the vapor pressure of the pure solvent (P_solvent).
Step 4: Use the formula from Raoult's Law: P_solution = X_solvent * P_solvent.
Step 5: Rearrange the formula to find the mole fraction of the solvent: X_solvent = P_solution / P_solvent.
Step 6: Substitute the values into the formula: X_solvent = 80 mmHg / 100 mmHg.
Step 7: Calculate X_solvent: X_solvent = 0.8.
Step 8: Find the mole fraction of the solute (X_solute) by using the formula: X_solute = 1 - X_solvent.
Step 9: Substitute the value of X_solvent: X_solute = 1 - 0.8.
