Molecular orbital theory, bond order, bond length, bond energy
- Given below are two statements :Statement I : A hypothetical diatomic molecule with bond order zero is quite stable.Statement II : As bond order increases, the bond length increases.In the light of the above statements, choose the most appropriate an… Answer: 2. Both Statement I and Statement II are false Key idea: bond order measures net bonding; it links to stability and bond length. Sta... 1
- The correct order of energies of molecular orbitals of N_2 molecule, is : Answer: 2. σ 1s<σ^* 1s<σ 2s<σ^* 2s<(π 2p_x=π 2p_y)<σ 2p_z<(π^* 2p_x=π^* 2p_y)<σ^* 2p_z Key idea: For molecules with 14 or fewer electrons (... 1
- Which amongst the following is incorrect statement ? Answer: 1. O₂^+ ion is diamagnetic. Key idea: write MO configurations and count unpaired electrons. O₂^+ has 15 electrons, with one electron... 1
- Identify a molecule which does not exist. Answer: 1. He ₂ A molecule exists only if its bond order (from molecular orbital theory) is greater than zero. He₂ : 4 electrons, σ1s²σ^*1s²... 1
- Which of the following diatomic molecular species has only π bonds according to Molecular Orbital Theory ? Answer: 3. C ₂ Write the MO configuration for each molecule. C₂ (12 electrons): σ_1s²σ_1s^(*2)σ_2s²σ_2s^(*2)π_2p⁴ . The 2p electrons occupy... 1
- Consider the following species :CN^+, CN^-, NO and CNWhich one of these will have the highest bond order ? Answer: 3. CN ^- Count electrons and fill the molecular orbitals. CN^- : 14 electrons, bond order 3 (isoelectronic with N₂ , CO). CN: 13 ele... 1
- Which one of the following pairs of species have the same bond order ? Answer: 2. CN^-, CO Key idea: compare bond orders from molecular orbital theory (isoelectronic species have equal bond orders). CN^- and CO... 1