NEET Solved Paper 2019 Question 35
Question: Which of the following reactions are disproportionation reaction? [NEET 5-5-2019]
(i) $ 2C{u^{+}}\to Cu^{2}+Cu^{0} $
(ii) $ 3Mn{O_4}^{2+}+4{H^{+}}\to 2Mn{O_4}^{-}+MnO _2 $ $ +2H _2O $
(iii) $ 2KMnO _4\xrightarrow{\Delta }K _2MnO _4+MnO _2 $ $ +O _2 $
(iv) $ 2MnO_4^{-}+3M{n^{2+}}+2H _2O\to 5MnO _2 $ $ +4{H^{\oplus }} $
Select the correct option from the following:
Options:
A) (i), (iii) and (iv)
B) (i) and (iv) only
C) (i) and (ii) only
D) (i), (ii) and (iii)
Show Answer
Answer:
Correct Answer: B
Solution:
$ {{\overset{+7}{\mathop{KMnO}}}_4}\to K _2{{\overset{+6}{\mathop{MnO}}} _4}+{{\overset{+4}{\mathop{MnO}}}_4} $
$ C{u^{+1}}\to C{u^{+2}}+Cu^{0} $ Disproportionate $ Rx^{n} $
$ \overset{+6}{\mathop{Mn}},O_4^{-2}\to \overset{+7}{\mathop{Mn}},{O_4}^{-}+4\overset{+4}{\mathop{Mn}},O _2 $ (i), (ii) only
