Question

A molecule of alkene has the chemical formula C3H4. How many carbon-carbon double bonds are present in the molecule?

A) One
B) Two
C) Three.

Answer 1

A molecule of Alkene has the chemical formula C3H4, there is one carbon to carbon double bond in the molecule.

Answer 2

For all of Carbon's valencies to be satisfied:
H₂C = C = CH₂
Thus, the answer is:
B) Two