Chemical problems. On the reduction and oxidation of metals. ...

Remember this formula: high oxygen and low return, turn in the middle. It means that the highest valence state of ions is only oxidation state, the lowest valence state is only reduction state, and the middle valence state has two properties. 1. Because the explanation of oxidizability and reducibility in high school chemistry can be judged from the valence change of elements, all particles that can realize the corresponding valence change can show corresponding chemical properties.

Among them, cations can reduce the price to show oxidation, while anions can increase the price to show reduction.

If a substance wants to show oxidation, it must be able to get electrons, so that its valence can be reduced. Because the valence of metal elements in a simple metal is 0, there is no negative valence of metal, so the valence of metal elements in a simple metal can only increase, not decrease, so it only decreases.