Video narration
How can one element be oxidized and reduced at the same time? Imagine identical game pieces starting with the same score. In one round, some lose points while others gain them. They are the same kind of piece, but they take different paths. Chemistry works the same way. Oxidation means an element's oxidation state increases; reduction means it decreases. The key is that different atoms of that element make those changes. One group moves upward; another moves downward. That pattern is called disproportionation: the same element is oxidized and reduced in one reaction. Take hydrogen peroxide: 2 H2O2 becomes 2 H2O plus O2. Oxygen starts at oxidation state minus one. Some oxygen atoms end at minus two in water-reduction. Others end at zero in O2-oxidation. So the answer is not that one atom does both. Different game pieces of the same kind take opposite paths. That is disproportionation.