Most carbon-based molecules are classified as
ï§Carbon-based molecules are called organic compounds. ï§â¯By sharing electrons, carbon can ââ¯bond to four other atoms and ââ¯branch in up to four directions. ï§â¯compounds composed of only carbon and hydrogen are called hydrocarbons. ï§â¯A carbon skeleton is a chain of carbon atoms that can be ââ¯branched or ââ¯unbranched.