Redox Reactions And Electrochemistry Ques 356
Question: An element A in a compound ABD has oxidation number $ {{A}^{{{n}^{-}}}} $ . It is oxidised by $ Cr_2O_7^{2-} $ in acid medium. In the experiment $ 1.68\times {{10}^{-3}} $ moles of $ K_2Cr_2O_7 $ was used for $ 3.26\times {{10}^{-3}} $ moles of ABD. The new oxidation number of A after oxidation is:
Options:
A) 3
B) 3-n
C) n-3
D) +n
Show Answer
Answer:
Correct Answer: B
Solution:
[b] Meq. of $ K_2Cr_2O_7=Meq. $ of ABD n-factor of $ K_2Cr_2O_7 $ in acidic medium =6 $ 6\times 1.68\times {{10}^{-3}}=x\times 3.26\times {{10}^{-3}} $ $ x=3 $
$ \Rightarrow $ New oxidation state of $ {{A}^{-n}} $ will be =-n+3