What type of hybridisation is involved in the formation of the `C -=C ` bond?

Explanation

To determine the type of hybridization involved in the formation of the C≡C bond, we can follow these steps:

### Step 1: Understand the Structure of Ethyne
Ethyne (C2H2), also known as acetylene, contains a carbon-carbon triple bond (C≡C). Each carbon atom in ethyne is bonded to one hydrogen atom and is involved in a triple bond with the other carbon atom.

### Step 2: Identify the Bonds in the Triple Bond
A triple bond consists of one sigma (σ) bond and two pi (π) bonds. In the case of the C≡C bond:
- The first bond (σ) is formed by the head-on overlap of orbitals.
...