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Calculate the boiling of a solution 0.61...

Calculate the boiling of a solution 0.61 g of benzoic acid in 5 g of `CS_(2)` assuming 84% dimerisation of acid. The boiling ad `K_(b)of CS(2) and 46^(@)C and 2.3 K kg mol^(-1)` respectivley.

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Calculation of Van't Hoff factor
Benzoic acid dimerises in `CS_(2)` as follows:
`2C_(6)G_(5)COOHhArr(C_(6)H_(5)COOH)_(2)`
`alpha=84%=0.84, n=1/2`
`alpha=((i-1))/((1//n-1)),0.84=((i-1))/((1//2-1))`
i=-0.42+0.58
Calculation of molality of solution
`" Molality (m)"= ("Mass of benzonic acid")/("Molar mass" xx "Mass of" CS_(2) "in kg")`
`=((0.61g)//(122 g mol^(-1)))/((0.005 kg))= 0.1 mol kg^(-1)`
Calculation of the boiling of the solution
`DeltaT_(b)=ixxK_(b)xxm=(0.58)xx(2.3 k kg mol^(-1))xx(0.1 mol kg^(-1))`
`=0.1334 K=0.1334^(@)C`
Boiling point of the solution=(46.2+0.1334)
=`46.3334^(@)C`
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