Question

Match the bond order for the following molecules.

List -I		List-II
A	$Li_2$	i	3
B	$N_2$	ii	1.5
C	$Be_2$	iii	1.0
D	$O_2$	iv	0
		v	2

The correct answer is

• A. (A)-(ii), (B)-(iii), (C)-(i), (D)-(v)
• B. (A)-(iii), (B)-(i), (C)-(iv), (D)-(v)
• C. (A)-(iv), (B)-(i), (C)-(v), (D)-(iii)
• D. (A)-(iii), (B)-(ii), (C)-(v), (D)-(i)

Answer 1

Answer: (B)

Bond order the number of chemical bonds between a pair of atom. So, $( B.O )$

$Li _{2}= Li - Li \,\,\,\,\,(1)$

$N _{2}= N \equiv N \,\,\,\,\,(3) $

$Be _{2}= Be$ ( No bond) $(0)$

$O _{2}= O = O (2)$

Note Zero bond order means the molecule is too unstable and so it will not exist.

Electrons will fill according to the energy levels of the orbitals.