JEE Main On 08 April 2018 Question 24
Question: The oxidation states of $ Cr $ in $ [\text{ Cr(}{H_2}O{{)}_6}]\text{ C}{l_3} $ , $ [\text{ Cr(}{C_6}{H_6}{{)}_2}] $ , and $ {K_2}[\text{ Cr(CN}{{)}_2}{{\text{(O)}}_2}\text{(}{O_2}\text{)(N}{H_3}\text{) }] $ Respectively are: [JEE Main Online 08-04-2018]
Options:
A) $ \text{+3, 0, and +6} $
B) $ \text{+3, 0, and +4} $
C) $ \text{+3, +4 and +6} $
D) $ \text{+3, +2 and +4} $
Show Answer
Answer:
Correct Answer: A
Solution:
$ \Rightarrow [Cr{{(H _2O)}_6}]Cl _3\to $ be oxidation state of chromium $ \text{x+6(0)=+3} $ $ \text{x = +3} $
$ \Rightarrow $ $ [Cr{{(C _6H _6)}_2}] $ $ x+2(0)=0 $ $ x=0 $
$ \Rightarrow {k_2}[\text{ Cr(CN}{{)}_2}{{\text{(O)}}_2}\text{(}{O_2}\text{)(N}{H_3}\text{) }] $
$ x-2+2(-2)+1(-2)+0=-2 $
$ x-2-4-2=-2 $ $ x-6=0 $ $ x=+6 $
