Describe how oxidation and reduction involve electrons, change oxidation numbers, and combine in oxidation-reduction reactions.

In a redox reaction, the gain and loss of electrons by the elements are termed oxidation and reduction.

Oxidation is the process in which in order to form the ions and chemical bonds, the elements lose the electrons. The electron loss will result in the element attaining a stable, complete electronic configuration.

The reduction is the process of gain of electrons by the element in the process of bond formation. The change in oxidation number describes the degree of loss or gain of electrons by the atom. For example, in a reaction, if oxygen gains 2 electrons, then the oxidation number of oxygen will be 2.

The oxidation and reduction reaction takes place simultaneously. In the process of oxidation if an element is oxidized and loses one electron, then the other element gets reduced by gaining the electron.

For more information, refer to the link:

link

they are all solids.