Question

If N is the Avogadro's number then number of valence electrons in 4.8g of oxygen ions is?

Answer 1

You have got (somehow) a `4.8*g` mass of oxide ions....

Explanation:

That is you got `4.8*g` with respect to `O^(2-)`...

And each `O^(2-)` ion possesses 8 valence electrons. Agreed?

And so we take the product...`"number of valence electrons"`

`=(4.8*g)/(16.00*g*mol^-1)xx8*"valence electrons"*mol^-1xxN_A*"electrons"`...

where `N_A-=6.022xx10^23`

and so we got....`2.4xxN_A*"electrons"`...