Question - 2.10 - Boiling point of water at 750 mm Hg is 99.63°C. How much sucrose is to be added to 500 g of water such that it boils at 100°C.
Elevation of boiling point
Mass of water (W A) = 500 g
Molar mass (M B) of sucrose (C 12H22 O11 ) = 12 x 12 + 1 x 22 + 16 x 11 = 342 g mol – 1
Molal constant for water (Kb ) = 0.52 K kg mol – 1
Therefore, W B = ?
We know that,
Thus, 121.67 g of sucrose to be added.