Question

Give reasons for the following in one or two sentences "The central carbon-carbon bond in 1,3-butadiene is shorter than that of n-butane".

Answer 1

1, 3-butadiene shows the property of resonance

So bond between second and third C-atoms show partial

double bond character. Hence, bond length is shorter than

C-C bond in n-butane (due to presence of resonance.)