Redox Reactions And Electrochemistry Ques 106
Question: The oxidation number of sulphur in $ H_2S_2O_7 $ and iron in $ K_4Fe{{(CN)}_6} $ is respectively [AIIMS 2000]
Options:
A) + 6 and + 2
B) + 2 and + 2
C) + 8 and + 2
D) + 6 and + 4
Show Answer
Answer:
Correct Answer: A
Solution:
$ \overset{*,}{\mathop{H_2S_2O_7}}, $
$ 2\times (+1)+2\times x+7\times (-2)=0 $
$ +2+2x-14=0 $ $ 2x=14-2=12 $
$ x=\frac{12}{2}=+6forS $
$ K_4\overset{*}{\mathop{Fe}},{{(CN)}_6} $
$ 4\times (+1),x+6\times (-1)=0 $ $ 4+x-6=0 $ $ x=6-4=+2forFe $ .
