Question

How many covalent bonds does carbon form in neutral compounds?

Answer 1

The carbon atom has 4 valence electrons, and is most stable when it forms 4 covalent bonds with other atoms.

Explanation:

`CH_4`, `H_3C-CH_3`, `H_2C=CH_2`; in 2 of these examples, the 4 valence electrons on `C` are formally paired with the `1` electron on `H` to form form 4 covalent bonds. In the one instance, ethylene, each carbon centre shares 2 electrons with the other carbon to form an unsaturated bond, a `C=C` double bond.

For anionic species, there are 5 electrons presumed to be "owned" by the carbon centre, e.g. `H_3C:^(-)Li^+`, and here carbon has a FORMAL negative charge.