An acid has several definitions one would be that it is a proton donor and an electron donor. Also, it said to produce an H+ ion when in solution. For nitric acid in solution, it dissociates into ions which are NO- ions and H+ ions. So, it must be an acid. It has a dissociation reaction:
HNO3 = H+ + NO3-
The charge of the cadmium cation is +2
