Question

Arrange the following bonds in decreasing order of bond strength : 

C-N, C=N, C≡N

Answer 1

C≡N > C=N > C-N

Note : 

Average bond lengths for some single, double and triple bonds :

Type of bond	Covalent bond length (pm)
O-H	96
C-H	107
N-O	136
C-O	143
C-N	143
C-C	154
C=C	121
N=O	122
C=C	133
C=N	138
C≡N	116
C≡C	120

Type of bond	Covalent bond length (pm)
H2(H-H)	74
F2(F-F)	144
Cl2(Cl-Cl)	199
Br2(Br-Br)	228
I2(I-I)	267
N2(N≡N)	109
O2(O-O)	121
HF (H-F)	92
HCl (H-Cl)	127
HBr (H-Br)	141
HI (H-I)	160