Give an example to show the effect of concentration of nitric acid on the formation of oxidation product.

Example Reactions:

1. 4Zn +10HNO3(dil) → 4Zn(NO3)2 + NH4NO3 + 3H2O

2. 4Zn +10HNO3(dil) → 4Zn(NO3)2 + N2O + 5H2O

3. 4Zn +4HNO3(conc.) → Zn(NO3)2 + NO2 + 2H2O