The IUPAC name for the compound $ClCH_{2}CH_{2}OH$ is

Step 1: Analyze the question We need the IUPAC name of ClCH₂CH₂OH. Count the carbons, find the principal functional group, then number the chain.

Step 2: Concept IUPAC naming rules:

• The parent chain is the longest carbon chain. Here there are 2 carbons, so the parent is ethane.
• The principal functional group (the –OH, which gives an alcohol, suffix -ol) gets the lowest possible number.
• Substituents such as chlorine (prefix chloro-) are numbered according to that chain numbering.

Step 3: Solution Structure: Cl–CH₂–CH₂–OH

1. Two carbons means ethane, so the parent is ethanol.
2. Number from the end nearest the –OH group, so the carbon bearing –OH is C-1. • C-1: CH₂OH • C-2: CH₂Cl
3. The chlorine is on C-2, so the name is 2-chloroethanol.

Why not the others?

• A and B say "propanol", which would need 3 carbons, but we have only 2.
• C says 1-chloroethanol, which would be Cl and OH on the same carbon (CH₃CH(Cl)OH). That is a different compound.

Answer: D. 2-chloroethanol

Tip: In naming alcohols, the –OH always gets the lowest number. Then place the other substituents using that numbering. Always count carbons first, because that removes wrong options like "propanol" immediately.