On addition to a small amount of KMnO4 to concentrated H2SO4, a green oily compound is obtained which is highly explosive in nature. Identify the compound from the following.

1. Mn2O7

2MnO2

3MnSO4

4Mn2O3

Hint: In the product, Mn is present in a +7 oxidation state.

In addition of KMnO4, to concentrated H2SO4, a green oily compound Mn2O7 is obtained which is highly explosive in nature. 

The reaction is as follows:

KMnO4 + 2H2SO4(conc.) →Mn2O7 + 2KHSO4 + H2O