Question

What kinds of ions do a sodium atom and a chlorine atom become when a valence electron is transferred from one to the other?

Answer 1

The chlorine atom is reduced; the sodium atom is oxidized.

Explanation:

Heat sodium metal up in an atmosphere of chlorine gas, and a redox reaction occurs; a transfer of electrons.

`Na rarr Na^+ + e^(-)`;

Sodium (gas) is oxidized.

`1/2Cl_2 + e^(-) rarr Cl^(-)`.

Chlorine gas is reduced.

Add these reactions together, and we get:

`Na + 1/2Cl_2 rarr NaCl`

This is certainly a redox reaction, and the individual reaction enthalpies may be precisely measured and defined.