What weight of glucose must be dissolved in $$100 \mathrm{~g}$$ of water to lower the vapour pressure by $$0.20 \mathrm{~mm} ~\mathrm{Hg}$$ ?
(Assume dilute solution is being formed)
Given : Vapour pressure of pure water is $$54.2 \mathrm{~mm} ~\mathrm{Hg}$$ at room temperature. Molar mass of glucose is $$180 \mathrm{~g} \mathrm{~mol}^{-1}$$
A. The elevation in boiling point temperature of water will be same for $0.1 \mathrm{M} \, \mathrm{NaCl}$ and $0.1 \mathrm{M}$ urea.
B. Azeotropic mixtures boil without change in their composition.
C. Osmosis always takes place from hypertonic to hypotonic solution.
D. The density of $32 \% \, \mathrm{H}_{2} \mathrm{SO}_{4}$ solution having molarity $4.09 ~\mathrm{M}$ is approximately $1.26 \mathrm{~g} \mathrm{~mL}^{-1}$
E. A negatively charged sol is obtained when KI solution is added to silver nitrate solution.
Choose the correct answer from the options given below :
Match List I with List II
List I | List II | ||
---|---|---|---|
A. | van't Hoff factor, i | I. | Cryoscopic constant |
B. | $$\mathrm{k_f}$$ | II. | Isotonic solutions |
C. | Solutions with same osmotic pressure | III. | $$\mathrm{\frac{Normal\,molar\,mass}{Abnormal\,molar\,mass}}$$ |
D. | Azeotropes | IV. | Solutions with same composition of vapour above it |
Choose the correct answer from the options given below :
In the depression of freezing point experiment
A. Vapour pressure of the solution is less than that of pure solvent
B. Vapour pressure of the solution is more than that of pure solvent
C. Only solute molecules solidify at the freezing point
D. Only solvent molecules solidify at the freezing point
Choose the most appropriate answer from the options given below :