Which of the following is not correct with respect to bond length of the species?

Question

Which of the following is not correct with respect to bond length of the species? (A)  C2>C22-  (B)  B2+>B2  (C)  Li2+>Li2  (D)  N2+>N2

Tardigrade Admin · Accepted Answer

Greater the bond order, shorter is the bond length.

∴

B o n d or d er \propto \frac{1}{b o n d l e n g t h}

(i) Electronic configurations and bond orders of

C_{2}

and

C_{2}^{2 -}

ions:
EC of

C_{2} = KK σ 2 s^{2}, σ^{*} 2 s^{2}, π 2 p_{x}^{2}, π 2 p_{y}^{2}

Bond order

= \frac{1}{2} (6 - 2) = 2

EC of

C_{2}^{2 -} = KK σ 2 s^{2}, σ^{*} 2 s^{2}, π 2 p_{x}^{2}, π 2 p_{y}^{2}, σ 2 p_{z}^{2}

Bond order

= \frac{1}{2} (8 - 2) = 3

∴

The order of bond lengths:

B_{2}^{+} > B_{2}

(ii) Electronic configurations and bond orders of

B_{2}^{+}

and

B_{2}

EC of

B_{2} = KK σ 2 s^{2}, σ^{*} 2 s^{2}, π 2 p_{x}^{1}, π 2 p_{x}^{1}, π 2 p_{1}^{y}

Bond order

= \frac{1}{2} (4 - 2) = 1

EC of

B_{2}^{+} = KK σ 2 s^{2}, σ^{*} 2 s^{2}, π 2 p_{x}^{1}

Bond order

= \frac{1}{2} (3 - 2) = \frac{1}{2}

∴

The order of bond lengths:

B_{2}^{+} > B_{2}

(iii) Electronic configurations and bond orders of

L i_{2}

and

L i_{2}^{+}

EC of

L i_{2} = KK σ 2 s^{2}

Bond order

= \frac{1}{2} (2 - 0) = 1

EC of

L i_{2}^{+} = KK σ 2 s^{1}

Bond order

= \frac{1}{2} (1 - 0) = \frac{1}{2}

∴

The order of bond lengths:

L i_{2}^{+} > L i_{2}

(iv) Electronic configurations and bond orders of

N_{2}

and

N_{2}^{+}

EC of

N_{2} = KK σ 2 s^{2}, σ^{*} 2 s^{2}, π 2 p_{x}^{2}, π 2 p_{y}^{2}, σ 2 p_{z}^{2}

Bond order

= \frac{1}{2} (8 - 2) = 3

EC of

N_{2}^{+} = KK σ 2 s^{2}, σ^{*} 2 s^{2}, π 2 p_{x}^{2}, π 2 p_{y}^{2}, σ 2 p_{z}^{1}

Bond order

= \frac{1}{2} (7 - 2) = 2.5

∴

The order of bond lengths

= N_{2}^{+} > N_{2}

(v) Electronic configurations and bond orders of

O_{2}

and

O_{2}^{-}

: EC of

O_{2} = KK σ 2 s^{2}, σ^{*} 2 s^{2}, σ 2 p_{z}^{2}, π 2 p_{x}^{2}

π 2 p_{y}^{2}, π * 2 p_{x}^{1}, π * 2 p_{y}^{1}

Bond order

= \frac{1}{2} (8 - 4) = 2

EC of

O_{2}^{-} = KK σ 2 s^{2}, σ * 2 s^{2}, π 2 p_{z}^{2}, π 2 p_{x}^{2}, π 2 p_{y}^{2},

π * 2 p_{x}^{2}, π * 2 p_{y}^{1}

Bond order

= \frac{1}{2} (8 - 5) = 1.5

∴

The correct order of bond lengths

= O_{2}^{-} > O_{2}

Q. Which of the following is not correct with respect to bond length of the species?

$C_{2} > C_{2}^{2 -}$

$B_{2}^{+} > B_{2}$

$L i_{2}^{+} > L i_{2}$

$N_{2}^{+} > N_{2}$

$O_{2} > O_{2}^{-}$

Q. Which of the following is not correct with respect to bond length of the species?

C2​>C22−​

B2+​>B2​

Li2+​>Li2​

N2+​>N2​

O2​>O2−​

$C_{2} > C_{2}^{2 -}$

$B_{2}^{+} > B_{2}$

$L i_{2}^{+} > L i_{2}$

$N_{2}^{+} > N_{2}$

$O_{2} > O_{2}^{-}$