KBr is 80% dissociated in aqueous solution of 0.5 m concentration (Given `K_(f)=1.86 " K kg" mol^(-1))`. The solution freezes at :
KBr is 80% dissociated in aqueous solution of 0.5 m concentration (Given `K_(f)=1.86 " K kg" mol^(-1))`. The solution freezes at :
A. 271.326 K
B. 272 K
C. 270.5 K
D. 268.5 K.
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Correct Answer - a
`alpha=(i-1)/(n-1)or 0.8=(i-1)/(2-1)
i=1.28, DeltaT_(f)=iK_(f)m`
` =1.28xx(1.86 K kg mol^(-1))xx(0.5 mol kg^(-1))`
=1.674 K.
f.p. of solution=(273-1.674) = 271.326 K
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