Rules for dot-and-cross diagrams:
1. Show outer shell electrons only.
2. Work out whether the bonds are ionic (between a metal and a non-metal) or covalent (between only non-metals)
- Use square brackets and label the charge outside of these brackets, e.g. + or 2-
- Show the ions after they have transferred electrons, not before
- If there is more than one ion, make this clear, e.g. in MgCl2, draw…