B

B. E. Douglas, D. H. McDaniel, J. J. Alexander, Concepts and Models of Inorganic Chemistry, 3^rd edition, John Wiley & Sons, New York, 1994, page 196.

Problem 4.1

Give the bond order and the number of unpaired electrons for Be₂⁺, B₂⁺, C₂⁺, O₂, O₂⁺, O₂^-_, O₂^2-_.

Answer:

Use Table 4.1

Electron Configuration Bond Order Unpaired Electrons

Be₂⁺ _2s² _2s*¹ 0.5 1

B₂⁺ _2s² _2s*²_x,y¹ 0.5 1

C₂⁺ _2s² _2s*²_x,y³ 1.5 1

O₂ _2s² _2s*²_pz² _x,y⁴_x,y*² 2 2

O₂⁺ _2s² _2s*²_pz² _x,y⁴_x,y*¹ 2.5 1

O₂^- _2s²_2s*² _pz²_x,y⁴ _x,y*³ 1.5 1

O₂^2- _2s²_2s*² _pz²_x,y⁴ _x,y*⁴ 1 0

	Electron Configuration	Bond Order	Unpaired Electrons
Be₂⁺	_2s² _2s*¹	0.5	1
B₂⁺	_2s² _2s*²_x,y¹	0.5	1
C₂⁺	_2s² _2s*²_x,y³	1.5	1
O₂	_2s² _2s²_pz² _x,y⁴_x,y²	2	2
O₂⁺	_2s² _2s²_pz² _x,y⁴_x,y¹	2.5	1
O₂^-	_2s²_2s² _pz²_x,y⁴ _x,y³	1.5	1
O₂^2-	_2s²_2s² _pz²_x,y⁴ _x,y⁴	1	0