Some Basic Concepts Of Chemistry Question 63
Question: 3.92 g of ferrous ammonium sulphate crystals are dissolved in 100 mL of water. 20 mL of this solution requires 18 mL of potassium permaganate during titration for complete oxidation. The weight of $ KMnO _4 $ present in one litre of the solution of
Options:
A) 3.47 g
B) 12.38 g
C) 1.23 g
D) 34.76 g
Show Answer
Answer:
Correct Answer: A
Solution:
[a] Normality of ferrous amm sulphate $ =\frac{3.92\times 1000}{392\times 100}=0.1 $ (Eq. wt of FAS is 392)
$ M _1V _1=M _2V _2 $ $ 20\times 0.1=18\times N _2 $
$ N _2=0.111 $ 1 g ev. of $ KMnO _4=31.6g $ 0.111 g ev. of $ KMnO _4=31.6\times 0.111=3.5g. $
