18 g glucose is added to 178.2 g water. The vapour pressure of water (in torr) for this aqueous solution is :
- (A)76.0
- (B)752.4✓ Correct
- (C)759.0
- (D)7.6
Answer: (B)
Solution
The glucose is mol and the water mol, so the solute mole fraction is . By Raoult's law the relative lowering of vapour pressure equals this, , so the drop is torr. The vapour pressure of the solution is torr.
JEE Main · 2016 · 03 Apr 2016 · Offline · Single correct option