Some Basic Concepts Of Chemistry Question 155
Question: About $ 6\times {10^{-3}} $ mol $ K _2Cr _2O _7 $ reacts completely with $ 9\times {10^{-3}} $ mol $ {X^{n+}} $ to give $ X{O^{-}}_3 $ and $ C{r^{3+}} $ . The value of $ n $ is:
Options:
A) 1
B) 2
C) 3
D) none of these
Show Answer
Answer:
Correct Answer: A
Solution:
[a] $ K _2Cr _2O _7+{X^{n+}}\to {X^{5+}}O_3^{-}+C{r^{3+}} $ $ 6\times {10^{-3}}\times 6=(5-n)\times 9\times {10^{-3}}\Rightarrow ,n=1 $
