text: I will try to show this using Copper as the metal in question:\n\nCu_(s) + 4HNO_3(aq) ---> Cu(NO_3)_2(aq) + 2NO_2(g) + 2H_2O_(L)\n\nWhere (s) is solid, (aq) is an aqueous solution, and (g) is gas.\n\nWhen the nitric acid hits the copper, it generates (amongst other things), nitrogen dioxide, a noxious and insidious poison.