Direction (Q. Nos. 53): A solution of sucrose [M (mass) = 342] has been prepared In dissolving 68.4 g of sucrose in 1 kg of water. \[{{K}_{f}}\] for water is \[1.\,86\,kg\,\,mo{{l}^{-1}}\] and vapour pressure of water at 298 K is 0.024 atm. Assume density of the solution is 1 g/mL. |
A) 0.230 atm
B) 0.233 atm
C) 0.236 atm
D) 0.0239 atm
Correct Answer: D
Solution :
\[V=ls=l\times \] \[R=\rho \frac{l}{s}=\frac{\rho }{V}{{l}^{2}}\] Mass of solute \[\log \,R=\log \,\rho +2\,\log \,l-\log \,V\] Molecular mass of solute \[\frac{dR}{R}=0+\frac{2dl}{l}-0=2\frac{dl}{l}\]Wt. of solvent \[\frac{dR}{R}\] Molecular mass of solvent \[\frac{dl}{l}\] \[\frac{dR}{R}=2\times 2%=4%\] \[E=-\frac{d\phi }{dt}=-\frac{d}{dt}(6{{t}^{2}}-5t+1)\]You need to login to perform this action.
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