NEETChemistryChemical Bonding and Molecular Structure
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): The molecular orbital formed by the head-on overlap of 2p_z atomic orbitals (assuming Z as the internuclear axis) is symmetrical around the bond axis. Reason (R): Bonding molecular orbitals are formed by the constructive interference of electron waves and have lower energy than the combining atomic
Options
- ABoth (A) and (R) are correct and (R) is the correct explanation of (A)
- BBoth (A) and (R) are correct but (R) is not the correct explanation of (A)
- C(A) is correct but (R) is not correct
- D(A) is not correct but (R) is correct
Correct answer
B. Both (A) and (R) are correct but (R) is not the correct explanation of (A)
Step-by-step solution
Assertion (A) is correct because the head-on overlap of 2p_z orbitals (taking Z as the internuclear axis) results in a sigma ( ) molecular orbital, which is cylindrically symmetrical around the bond axis. Reason (R) is also correct because bonding molecular orbitals are indeed formed by the additive effect (constructive interference) of electron waves and possess lower energy than the isolated atomic orbitals. However, (R) is not the correct explanation of (A). The symmetry of the molecular orbital is due to the ge