# Question #b7b17

• Normal orbital-normal orbital ( ${H}_{2}$ Neither atom has to hybridize in this example. )
• Hybridized orbital-normal orbital ( $H C l$ Chlorine hybridizes in this example. )
• Hybridized orbital-hybridized orbital (the carbon-carbon $\sigma$ bond in ${C}_{2} {H}_{4}$ both carbon atoms in this example are hybridized.)
The answer to your question is tricky because when oxygen hybridizes it has the same number of unpaired electrons; so its' ability to react really isn't changed. The Oxygen might or might not hybridize in $C {O}_{2}$.