Chemistry

Problem

Which expression correctly defines the formal charge,

FC

, on an atom in a Lewis structure? a)

FC = \text{valence electrons} - [\text{non-bonding electrons} + \text{bonding electrons}]

FC = \text{non-bonding electrons} + \tfrac12 \times \text{bonding electrons} - \text{valence electrons}

FC = \text{(valence electrons in the free atom)} - [\text{non-bonding electrons} + \tfrac12 \times \text{bonding electrons}]

FC = \text{valence electrons} - \text{non-bonding electrons} + \tfrac12 \times \text{bonding electrons}