Which element is oxidized and which is reduced in each of the following reactions? (a)

Oxidation and reduction are chemical processes that involve the transfer of electrons between substances. Oxidation refers to the loss of electrons, resulting in an increase in oxidation state, while reduction involves the gain of electrons, leading to a decrease in oxidation state. These processes always occur simultaneously in a redox reaction, where one species is oxidized and another is reduced.

Oxidation states (or oxidation numbers) are a way to keep track of electron transfer in chemical reactions. Each element in a compound is assigned an oxidation state based on its electron configuration and bonding. Understanding oxidation states helps identify which elements are oxidized and reduced in a reaction, as the changes in these states indicate the flow of electrons.

Half-reactions are a method of breaking down redox reactions into two separate equations: one for oxidation and one for reduction. This approach allows for a clearer understanding of the electron transfer process. By analyzing half-reactions, one can easily determine which species is oxidized and which is reduced, facilitating the identification of changes in oxidation states.