Hydrogen And Its Compounds Question 239
Question: A 5.0 mL solution of $ H_2O_2 $ liberates 1.27 g of iodine from an acidified KI solution. The percentage strength of $ H_2O_2 $ is
Options:
A) 11.2
B) 5.6
C) 1.7
D) 3.4
Show Answer
Answer:
Correct Answer: D
Solution:
[d] $ H_2O_2\equiv KI\equiv I_2 $
$ mEqofH_2O_2=5\times N $
$ mEqofI_2=\frac{Weight}{E.w}\times 1000 $
$ \frac{1.27}{127}\times 1000=10mEq $
$ I_2=M.w=254 $
$ E.w=\frac{M.w}{2}=\frac{254}{2}=127 $
$ \therefore mEqofH_2O_2=mEqofI_2 $
$ 5\times N=10 $
$ \therefore N=2 $ 1 N of $ H_2O_2=1/7 $ % of $ H_2O_2 $ 2 N of $ H_2O_2 $ = 3.4% $ H_2O_2 $
BETA
