Question

Explain the formation of magnesium oxide with the help of electron dot structure?

Answer 1

there u go above is the structural formula and below is the dot digram

Answer 2

Here, Mg does not have a fully filled octet as you can see. What Mg does is instead of sharing the electrons, it donates them to oxygen, which allows oxygen to obtain a fully filled outer shell while it also makes Mg stable by forming a cation with fully filled outer shell. This means, it is an ionic bond and not a covalent one, so electron dot structure doesn't show a fully filled Mg shell.