In the compound HNO3 nitric acid , the oxidation state of nitrogen can be determined by considering the oxidation states of the other elements in the compound and the overall charge of the molecule.The oxidation state of hydrogen H is +1 and the oxidation state of oxygen O is -2. Since there are three oxygen atoms, the total oxidation state for oxygen in the compound is -6. There is one hydrogen atom, so its total oxidation state is +1.The overall charge of the HNO3 molecule is neutral 0 . Therefore, the oxidation state of nitrogen N can be calculated using the following equation:Oxidation state of N + Oxidation state of H + Oxidation state of O = 0Let x be the oxidation state of nitrogen. Then the equation becomes:x + +1 + -6 = 0Solving for x:x - 5 = 0x = +5So, the oxidation state of nitrogen in HNO3 is +5.