JEE Main 2022 Chemistry question
When a certain amount of solid A is dissolved in 100 g of water at 25°C to make a dilute solution, the vapour pressure of the solution is reduced to one-half of that of pure water. The vapour pressure of pure water is 23.76 mmHg. The number of moles of solute A added is . (Nearest Integer)
Answer: 6
Solution
The vapour pressure is reduced to one-half, so (P° − / = 1 = /, i.e. = = mol.