Drawing Lewis Dot Structures for Ionic Compounds

Ionic Bonding involves: TRANSFER of valence e- from metal atom to non-metal atom:

2 step process: 1) transfer of e- from metal to non-metal atoms result: +/- IONS form 2) electrostatic attraction between +/- ions result: ionic bond forms

[Na]+1[ Cl ]-1 NaCl • • • • • • • • remember: Lewis diagrams show valence electrons!

Predicting Ionic Compounds What is the ionic compound formed from calcium and iodine? calcium: metal with 2 valence electrons - loses both electrons  [Ca]+2 iodine: non-metal with 7 valence electrons - gains 1 electron  [ ‍I ]-1 •• • • • • •• how many iodine ions are needed to make a neutral compound? 2

Lewis Diagram of calcium iodide (CaI2) [Ca]+2[:I:]-1[:I:]-1 or [:I:]-1[Ca]+2[:I:]-1 note: total charge MUST add up to zero since compounds are neutral ·· ·· ·· ·· ·· ·· ·· ··