Question

Zn gives H2 gas with H2SO4 and HCI but not with HNO3 because (a) Zn act as oxidising agent when react with

Answer 1

Nitric acid is a very strong oxidising agent and hence it leads to the addition of oxygen to another substance. Thus when hydrogen is formed due to addition of nitric acid on zinc metal it oxidises hydrogen to water and thus the reaction becomes  

Zn + 4HNO3 ---> Zn(NO3)2 + 2NO2 +2H2O