Neet Solved Paper 2015 Question 23
Question: Which one of the following electrolytes has the same value of van’t Hoffs factor (2) as that of $ Al _2{{( SO _4 )}_3} $ (if all are 100% ionized)?
Options:
A) $ K _2SO _4 $
B) $ K _3[Fe{{(CN)}_6}] $
C) $ Al{{(NO _3)}_3} $
D) $ K _4[Fe{{(CN)}_6}] $
Show Answer
Answer:
Correct Answer: D
Solution:
$ Al _2{{(SO _4)}_3}2A{l^{3+}}+3SO_4^{2-} $ Value of Van?t Hoff?s factor $ (i)=5 $
(a) $ K _2SO _42{K^{+}}+SO_4^{2-} $ $ (i=3) $
(b) $ K _3[Fe{{(CN)}_6}]3{K^{+}}+{{[Fe{{(CN)}_6}]}^{3-}} $ $ (i=4) $
(c) $ Al{{(NO _3)}_3}A{l^{3+}}+3NO_3^{-} $ $ (i=4) $
(d) $ K _4[Fe{{(CN)}_6}]4{K^{+}}+{{[Fe{{(CN)}_6}]}^{3-}} $ $ (i=5) $
Therefore, $ K _4[Fe{{(CN)}_6}] $ has same value of i that of $ Al _2{{(SO _4)}_3} $ i.e. $ i=5 $
