When 2-pentene is treated with \(\mathrm{Cl}_{2}\) in methanol, three products are formed. Account for the formation of each product (you need not explain their relative percentages).

We are given that 2-pentene reacts with \(\mathrm{Cl}_{2}\) in methanol. The structure of 2-pentene is CH3CH=CHCH2CH3. The double bond is between the second and third carbons, which means it is an alkene.

The reaction involves the addition of a chlorine molecule to the double bond of the 2-pentene molecule. This will result in the formation of various products depending on which carbons the chlorine atoms bond to.

The double bond in the 2-pentene can break and form three possible products with the addition of Cl₂. 1) Product 1: Both chlorine atoms bond to the second carbon atom of the 2-pentene molecule, resulting in the formation of 1,1,2-trichloropentane (CH3CCl2CHCH2CH3). 2) Product 2: One chlorine atom bonds to the second carbon atom and the other chlorine atom bonds to the third carbon atom of the 2-pentene molecule, resulting in the formation of 1,2-dichloropentane (CH3CHClCHClCH3). 3) Product 3: Both chlorine atoms bond to the third carbon atom of the 2-pentene molecule, resulting in the formation of 1,1,3-trichloropentane (CH3CHCl2CHCH3).

1) The formation of 1,1,2-trichloropentane occurs when both chlorine atoms of the \(\mathrm{Cl}_{2}\) molecule attack the second carbon atom of the 2-pentene molecule simultaneously. 2) The formation of 1,2-dichloropentane takes place when one chlorine atom from the \(\mathrm{Cl}_{2}\) molecule attacks the second carbon atom, and the other chlorine atom attacks the third carbon atom of the 2-pentene molecule. This is possible due to the electrophilic addition of chlorine, where one chlorine atom acts as an electrophile and the other acts as a nucleophile. 3) The formation of 1,1,3-trichloropentane occurs when both chlorine atoms of the \(\mathrm{Cl}_{2}\) molecule attack the third carbon atom of the 2-pentene molecule simultaneously. In summary, the three products formed when 2-pentene is treated with \(\mathrm{Cl}_{2}\) in methanol are 1,1,2-trichloropentane, 1,2-dichloropentane, and 1,1,3-trichloropentane. The formation of these products can be explained by the electrophilic addition of chlorine and the attack of chlorine atoms on different carbon atoms of the 2-pentene molecule.