A 3.4 g sample of H2O2 solution containing x% by mass requires x ml of a KMnO4 solution for complete oxidation under acidic medium. The molarity of KMnO4 solution is:
A
1.0 M
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
0.5 M
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
0.4 M
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
D
0.2 M
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution
The correct option is C 0.4 M Reaction of H2O2 with KMnO4 is as 5H2O2+2KMnO4+6H+→2K++2Mn2++8H2O+5O2
Now
100 gm of H2O2 soln. contains x gm H2O2
So 3.4 gm of soln. will have (x100)∗3.4
mass of H2O2 wiil be (x100)∗3.4 gm
The number of moles of H2O2 will be n1=givenmassmolecularmass
` = 0.001x`
Similarly moles of KMnO4 will be: n2 =Normality∗volume (in litres) =M×x1000
Now H2O2 and KMnO4 react in the ratio of 5:2 so n15=n22 0.001x5=0.001Mx2
giving Molarity = 0.4 M