Answer
The picture is attached below.
Work Step by Step
Pent-1-yne, when reacted with two equivalents of H-Cl, forms 2,2-dichloropentane.
The triple bond in pent-1-yne found between carbon number 1 and carbon number 2 breaks, and the bond between H−Cl also breaks. H and Cl atoms attach with these carbons and form a single bond with this carbon. Chlorine attaches to carbon number 2 whereas Hydrogen forms a bond with carbon number 1. The triple bond is converted into a double bond.
Further reacting with another H-Cl, the double bond between the carbon atoms breaks, and Hydrogen attaches to carbon number 1 whereas chlorine forms a bond with carbon number 2. The double bond is converted into a single bond and the resulting product is 2,2-dichloropentane.