A) The relative lowering of vapour pressure of a solution is equal to the mole fraction of the solute present in the solution
B) Passage of solute molecules towards solution side through semipermeable membrane is osmosis.
C) The boiling point of a solution is always lower than the solvent
D) The boiling point of a liquid is the temperature at which its vapour pressure becomes equal to 260 mm
Correct Answer: A
Solution :
[a] It is right. We know that the relative lowering of vapour pressure of a solution is equal to the mole fraction of the solute present in the solution. \[\frac{{{P}_{0}}-{{P}_{S}}}{{{P}_{0}}}={{x}_{1}}\] \[{{P}_{0}}=\]Vapour pressure of solvent \[{{P}_{S}}=\]Vapour pressure of solution \[{{x}_{1}}=\]Mole fraction of solute but the option [b], [c] and [d] are wrong, [b] Because movement of solvent molecules from the lower concentration side to higher concentration side through semipermeable membrane is known as osmosis. [c] According to elevation of b.p., the boiling point of solution is always higher than the solvent. [d]The boiling point of a liquid is the temperature at which its vapour pressure becomes equal to atmospheric pressure (760 mm).You need to login to perform this action.
You will be redirected in
3 sec