What is the hybridisation of each cabon in `H_(2) C = C = CH_(2)` ?

Explanation

The given structure is of allene `(C_(3)H_(4))`
`H_(2) overset(1)(C) = overset(2)(C) = overset(3)(C)H_(2)`
In allene, carbon atoms 1 and 3 are `sp^(3)` hybridised as each one of them is joined by a double bond. And, carbon atom 2 is sp-hybridised as it has two double bonds at each of its side. Therefore, the two `pi-` bonds are perpendicular to each other, in allene, as shown below.

`H_(a)` and `H_(b)` lie in the plane of paper while `H_(c) " and H_(d)` lie in a plane perpendicular to the plan of the paper. Hence, the allene molecule as a whole is non-planar