Provide the IUPAC name for the molecule below

The Correct Answer and Explanation is:

The molecule depicted in the image is 1-bromo-2-chloroethane.

Explanation

To determine the IUPAC name of the molecule, we follow the systematic rules established by the International Union of Pure and Applied Chemistry (IUPAC) for naming organic compounds.

Step 1: Identify the Longest Carbon Chain

The structure consists of a simple two-carbon alkane chain, which is ethane (C₂H₆) as the parent hydrocarbon.

Step 2: Identify and Name Substituents

The two substituents attached to the ethane chain are:

A bromine atom (Br).
A chlorine atom (Cl).

Halogens are treated as substituents in IUPAC nomenclature and are named as prefixes: bromo- for Br and chloro- for Cl.

Step 3: Number the Carbon Chain

The chain must be numbered to give the lowest possible numbers to the substituents. Numbering from left to right:

Carbon 1: Br (bromine)
Carbon 2: Cl (chlorine)

Thus, the substituents are on carbons 1 and 2 respectively. If you numbered it the other way, Cl would be on carbon 1 and Br on carbon 2 — the same set of numbers (1 and 2), so next we apply alphabetical order.

Step 4: Apply Alphabetical Order

When two or more different substituents are present, they are listed in alphabetical order regardless of position:

Bromo comes before chloro alphabetically.

Hence, the name is: 1-bromo-2-chloroethane.

Summary of Rules Applied:

Base chain: Ethane.
Substituents: Bromo and chloro.
Numbering: Chosen to give substituents the lowest possible numbers.
Alphabetical order: Bromo before chloro.

This systematic approach ensures that the name 1-bromo-2-chloroethane uniquely and unambiguously describes the compound.