Question

A molecule of alkene has the chemical formula C #H $. How many carbon-carbon double bonds are present in the molecule?

Answer 1

any molecule of alkene has always one or more double bonds in it.. as for the above form given,
if $ is less than 2#, we have multiple double or triple bonds..
if $ is equal to 2#, we have a single double bond..
if $ is greater than 2#, we will not have a double or triple bond..