Chemistry - CHEMICAL BONDING Question with Solution | TestHub
Number of CORRECT order(s) against the mentioned characteristic among the following.
(i) (IE)
(ii) (bond length)
(iii) (bond energy)
(iv) (C-O bond length)
(v) (Bond order)
(vi) (bond order)
Answer:
Solution:
(i) O₂ > O (IE): Incorrect. Ionization energy (IE) of O is greater than O₂. O is an atom, O₂ is a molecule.
(ii) O₂⁻ > O₂⁺ (bond length): Correct. Bond order (BO) of O₂⁻ is 1.5, BO of O₂⁺ is 2.5. Lower BO means longer bond length.
(iii) H₂⁺ = H₂⁻ (bond energy): Incorrect. H₂⁻ is unstable.
(iv) [V(CO)₆]⁻ > Cr(CO)₆ (C-O bond length): Correct. V is more electron-rich, leading to more back-bonding, weakening C-O bond and increasing its length.
(v) N₂⁺ > N₂⁻ (Bond order): Incorrect. BO of N₂⁺ is 2.5, BO of N₂⁻ is 2.5. They have the same bond order.
(vi) CO⁺ > CO (bond order): Correct. BO of CO is 3, BO of CO⁺ is 3.5. Removal of an electron from an antibonding orbital increases bond order.
Correct orders: (ii), (iv), (vi). Total = 3.
