Question

Sal drew the electron dot diagram of an aluminum atom as shown.

A l with 1 dot each above and right.

How should Sal correct his diagram?

He should add five more dots so that the atom obeys the octet rule.
He should add ten more dots so that all thirteen electrons are shown.
He should add a single dot below the symbol.
He should add one dot below and one dot to the left of the symbol.

Answer 1

Add a single dot below the symbol.

Aluminum (atomic number 13) is in group 13 and has 3 valence electrons, so its Lewis dot should show three single dots (one on three sides). Lewis diagrams show valence electrons only, not all 13 electrons, and the atom does not obey an octet.