Question

Select the correct statement(s) out of the following:
i) A sigma (s) bond is formed when two s-orbitals overlap.
ii) A pi (p) bond is formed when two p-orbitals overlap sideways.
iii) An sigma bond is weaker than pi bond.

• A. i and ii
• B. ii and iii
• C. i only
• D. ii only

Answer 1

The correct option is A i and ii

Pi bonds are usually weaker than sigma bonds. Quantum mechanics says this is because the orbital paths are parallel so there is much less overlap between the p-orbitals. Pi bonds happen when two atomic orbitals are in contact through two areas of overlap.

In a sigma bond, the electrons are in orbitals between the nuclei of the bonding atoms. Electron density is greatest between the nuclei. The electrons attract the nuclei and form a $\sigma$- bond- the strong covalent bond.

Option A is correct.