CHEM 101 Lecture Notes - Lecture 13: Formal Charge, Phosphorus Pentafluoride, Single Bond
Document Summary
Week 7 - lewis structures, formal charge, and exceptions to the octet rule. Exceptions of octet rule (atoms tend to gain, lose, or share electrons until they are surrounded by 8 valence electrons. ) With more than eight valence e- (expanded octet) Second period before carbon can make stable compounds with fewer than eight e- If filling the octet of the central atom results in a negative charge on the central atom and a positive charge on the outer atom, don"t fill the octet of the central atom. Experimental data confirm: structures with fewer formal charges better describe the actual structure of molecules. Single bond - one shared electron pair. Double bond - two shared electron pair. Triple bond - three shared electron pair. Formal charges - charge the atom would have if each bonding electron pair in a molecule were shared equally between its two atoms. Formal charge= valence electrons - (bonding electrons) - nonbonding electrons.
