Question

A solution of H2O2 is diluted to 10 times of its initial volume. 20ml of this diluted solution requires 10ml of 0.2N KMnO4 for complete oxidation. The volume strength if original H2O2 is ??

Answer 1

Answer:

We use law of equivalence:

Number of gram equivalence of H2O2=number of gram equivalence of KMnO4

Where number of gram equivalence=Normality*volume(in litres)

And normality=molarity*valence factor

For KMnO4 since reaction is in acidic medium, valence factor is 5:

Mn7++5e−→Mn2+

Since the equivalences are equal, we can take volume in ml instead.

So N×20=2×5×10

N=5 for H2O2

If you want concentration in volume strength,

Volume strength of H2O2=Normality*5.6

=5×5.6

=28vol

Explanation:

Answer 2

Law of equivalence:

Number of gram equivalence of H2O2=number of gram equivalence of KMnO4

Where number of gram equivalence=Normality*volume(in litres)

Normality=morality*valence factor

For KMnO4 since reaction is in acidic medium, valence factor is 5:   Mn7++5e−→Mn2+

Since the equivalences are equal, we can take volume in ml instead.

So, N×20=2×5×10

N=5 for H2O2

If you want concentration in volume strength,

Volume strength of H2O2=Normality*5.6

                                           =5×5.6

                                           =28vol