Skip to content
New summer mock series is live Attempt timed papers for SSC, banking, and engineering entrances with updated syllabi for this season. View exams

Question

The vapor pressure of pure water is 25 mm Hg at a certain temperature. A solution with a non-volatile solute has a vapor pressure of 23 mm Hg. If the solute’s molar mass is 60 g/mol, what is the mass of solute in 180 g of water?

Options

Choose one · Correct answer highlighted

Explanation

(p⁰ - p/p⁰) = xsolute . (25 - 23/25) = 0.08 . Moles of water = (180/18) = 10 . xsolute = (nsolute/nsolute + 10) = 0.08 . nsolute = 0.08 (nsolute + 10) , nsolute - 0.08 nsolute = 0.8 , 0.92 nsolute = 0.8 , nsolute ≈ 0.8696 . Mass = 0.8696 × 60 ≈ 52.18 g .