Question

Does oxygen 2- have 8 Valence electrons or 6 Valence electrons?

Answer 1

Look at the electronic structure of (i) the oxygen ATOM; and (ii) the oxide anion...

Explanation:

For the oxygen atom, `Z=8`, we conceive of the electronic structure at `1s^(2), 2s^(2), 2p^(4)`..for the oxide anion we insert TWO electrons into the valence shell, to give a full valence shell: `1s^(2), 2s^(2), 2p^(6)`...i.e. 10 electrons to fill the electronic shells, and a full valence shell....

Answer 2

`8` valence electrons

Explanation:

We know that a neutral oxygen atom has `8` electrons, which means that it has `2` electrons in the first shell and `6` electrons in the second shell, which is its valence shell.

For `O^(2-)`, it has gained `2` extra electrons, and so that will fill its outermost/valence shell, and will therefore have `2+6=8` valence electrons.