In the compound potassium nitrate KNO3 , the oxidation state of potassium K is +1 and the oxidation state of oxygen O is -2. Let's denote the oxidation state of nitrogen N as x.The overall charge of the compound is neutral, so the sum of the oxidation states of all elements in the compound should equal zero. Therefore, we can set up the following equation: +1 + x + 3 -2 = 0Now, we can solve for x:+1 + x - 6 = 0x - 5 = 0x = +5So, the oxidation state of nitrogen in potassium nitrate KNO3 is +5.