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 pm")(C_2H_6) gt underset(" 134 pm")(C_2H_4) gt underset("120 pm")(C_2H_2)`
Carbon,hydrogen bond lengths are :
`underset(" 100pm") (C_2H_6) gt underset(109" pm")(C_2H_4)gt underset(106"pm")(C_2H_2)`
Calculation of no. of Hybrid orbitals and Pure orbitals in carbon compounds

No. of pure orbitals `=2 (pi)` + No. of hydrogens