Question

What bond distance is expected to be longest?

1. A carbon-carbon bond with a bond order of 2
2. A carbon-carbon bond with a bond order of 3
3. A carbon-carbon bond with a bond order of O
4. carbon-carbon bond with a bond order of 1​

Answer 1

Bond length of C=C is largest(134 pm) because both the carbon atoms have same electronegativity. In case of C=O. and C=N carbon is bonded to highly electronegative atoms so bond length is shoreter as compared to C=C