What is the oxidation number of carbon in CH₄?

Core Concept

Hydrogen is assigned +1 when bonded to nonmetals, so the four hydrogens contribute +4 total. Because CH₄ is neutral, carbon must supply -4 to bring the sum to zero. Carbon sits below hydrogen in electronegativity, which is exactly why the shared electrons count toward carbon and give it the negative state. Assigning every other element first and solving for the unknown is the dependable routine for any oxidation-number problem.