In
covalent bond,
we studied how covalent molecules are formed. Now, it's your turn to try to answer some questions. If you have any difficulty
understanding the answers, please read our explanation of
formation of Cl2.
Explain the formation of HCl (hydrogen chloride).
Hydrogen and chlorine have one and seven valence electrons respectively. They share an electron pair so that hydrogen
can complete its duplet and chlorine can complete its octet.
Explain the formation of N2 (dinitrogen molecule).
Nitrogen has five valence electrons. Each nitrogen atom contributes 3 electrons to form three shared electron pairs.
By doing so, both of them complete their octets.
Explain the formation of H2O.
Hydrogen and oxygen have one and six valence electrons respectively. Oxygen shares one electron pair with each hydrogen
atom to complete its octet. Both hydrogen atoms complete their duplets.
Explain the formation of ammonia (NH3).
Nitrogen and hydrogen have five and one valence electrons respectively. Nitrogen shares three electron pairs —
one with each hydrogen atom — to complete its octet. The hydrogen atoms complete their duplets.
Explain the formation of methane (CH4).
Carbon has four valence electrons. Carbon shares four electron pairs — one with each hydrogen atom — to
complete its octet.
Explain the formation of ethene (C2H4).
Carbon has four valence electrons. In ethene, each carbon atom shares two electrons with other carbon, and other two
electrons with two hydrogen atoms.
