The major product would be 2-chloropentane. The mechanism is addition of hydrogen halides to alkenes.
Work Step by Step
The reaction follows the following steps: 1) Protonation of the pi bond forms a carbocation at the most substituted carbon. So the arrow originating from the double bond points towards H. Hydrogen attaches to the least substituted carbon. Because of this the attack chlorine leaves with the electrons involved in the bonding. 2) Then the halide attacks on the carbocation. So here $Cl^-$ attacks on the carbocation to give the Markovnikov product, 2-chloropentane.