Question

Question #03ed1

Answer 1

Atomic number of Sodium, `"Na"` is `11`. Orbital filling of its eleven electrons is shown below

`1s^2 2s^2 2p^6 3s^1`

In other words its electronic arrangement is `2,8,1`. Meaning it has single electron in the valence shell.

The completely filled shells corresponding to principal quantum number `n=1 and 2` are very stable.

We have observed that elements, while forming chemical bonds, follow the octet thumb rule. Atoms of main-group tend to combine in such a way that each atom has eight electrons in its valence shell, the same electronic configuration of a noble gas.

Sodium atom can either gain `7` electrons or lose`1` to attain this stable configuration. It is easier for a sodium atom to lose its extra electron and become a sodium cation having charge `+1` in the process
`" "Na -> Na^+ + e^-`