Question

The correct order of bond strength is ______.

Options

• \[\ce{O^-_2 < O2 < O^+_2 < O^{2-}_{2}}\]

• \[\ce{O^{2-}_2 < O^-_2 < O_2 < O^+_2}\]

• \[\ce{O^-_2 < O^{2-}_2 < O_2 < O^+_2}\]

• \[\ce{O^+_2 < O2 < O^-_2 < O^{2-}_{2}}\]

Answer 1

The correct order of bond strength is \[\underline{\ce{O^{2-}_2 < O^-_2 < O_2 < O^+_2}}\].

Explanation:

The bond strength is directly proportional to bond order, According to this, the correct order of bond strength is \[\ce{O^{2-}_2 < O^-_2 < O_2 < O^+_2}\].

	Total no. of electrons	Molecular orbital configuration	B.O = `1/2 ("N"_"b" - "N"_"a")`	Magnetic properties
\[\ce{O^+_2}\]	15	(σ1s)2 (σ*1s)2 (σ2s)2 (σ*2s)2 (σ2pz)2 (π 2px2 = π2py2) (π*2x1 = π*2py0)	`1/2`(10 - 5) = 2.5	Paramagnetic
\[\ce{O2}\]	16	(σ1s)2 (σ*1s)2 (σ2s)2 (σ*2s)2 (σ2pz)2 (π 2px2 = π2py2) (π*2x1 = π*2py1)	`1/2`(10 - 6) = 2	Paramagnetic
\[\ce{O^-_2}\]	17	(σ1s)2 (σ*1s)2 (σ2s)2 (σ*2s)2 (σ2pz)2 (π 2px2 = π2py2) (π*2x1 = π*2py1)	`1/2`(10 - 7) = 1.5	Paramagnetic
\[\ce{O^{2-}_2}\]	18	(σ1s)2 (σ*1s)2 (σ2s)2 (σ*2s)2 (σ2pz)2 (π 2px2 = π2py2) (π*2x1 = π*2py1)	`1/2`(10 - 8) = 1	Diamagnetic