They may have no bond polarity and does not contain

in the molecule so known as
saturated hydrocarbons.Preparation(i) From Grignard reagentRMgX alkyl magnesium halide (other examples of RMgX type molecules are RLi and R
2Cd)
This reaction is known as
Zere wittinoff’s method for estimation of active hydrogen in the molecule. Active hydrogen is the one which is attached to a highly electronegative element. eg., N,O,S etc. Hydrogen attached to alkyl groups like —CH
3, —C
2H
5 are never active due to less electronegativity of ‘C’ atom.