An aqueous solution contains 12.5% NaCl by mass. What mass of water (in grams) is contained in 2.5 L of the vapor above this solution at 55 °C? The vapor pressure of pure water at 55 °C is 118 torr. (Assume complete dissociation of NaCl.)

Verified step by step guidance

1. <insert step 1: Calculate the mass of NaCl in the solution. Assume a total mass of 100 g for simplicity, which means 12.5 g of NaCl and 87.5 g of water.>
2. <insert step 2: Determine the molality of the solution. Molality (m) is calculated as moles of solute (NaCl) per kilogram of solvent (water).>
3. <insert step 3: Use the van't Hoff factor (i) for NaCl, which is 2, to account for complete dissociation in the solution.>
4. <insert step 4: Apply Raoult's Law to find the vapor pressure of water above the solution. Raoult's Law is given by P_solution = X_solvent * P_pure, where X_solvent is the mole fraction of the solvent.>
5. <insert step 5: Calculate the mass of water in the vapor phase using the ideal gas law or other appropriate methods, considering the vapor pressure and volume of the vapor.>