Write the decreasing order of (a) carbon-carbon and (b) carbon- hydrogen bond lengths in ethane, ethylene and acetylene molecules.

Explanation

Carbon, carbon bond lengths are:
` underset(154 p m)(C_2 H_6 ) gt underset(134 p m) (C_2 H_4) gt underset(120 p m)(C_2H_2)`
Carbon, hydrogen bond lengths are :
` underset( 110 p m) (C_2 H_6) gt underset( 109 p m) (C_2 H_4) gt underset(106 p m) (C_2 H_2)`