Which of the following compounds contains a chiral carbon atom?

• A. ${\mathrm{CH}}_3\mathrm{CH}\left(\mathrm{Br}\right)\mathrm{CH}\left(\mathrm{Cl}\right){\mathrm{CH}}_3$
• B. ${\mathrm{CH}}_3{\mathrm{CH}}_2{\mathrm{CH}}_2{\mathrm{CH}}_3$
• C. ${\mathrm{CH}}_3\mathrm{COOH}$
• D. ${\mathrm{CH}}_3\mathrm{CH}\left(\mathrm{OH}\right){\mathrm{CH}}_3$

Answer: (A)

Verified step by step guidance

1. Recall that a chiral carbon atom (also called a stereocenter) is a carbon atom bonded to four different groups, making it asymmetric and non-superimposable on its mirror image.
2. Examine each compound and identify the carbon atoms, then check the substituents attached to each carbon to see if any carbon has four distinct groups.
3. For the first compound, look at the carbon bonded to Br and Cl substituents; determine if this carbon is attached to four different groups (e.g., Br, Cl, a hydrogen, and a carbon chain).
4. For the second compound (a straight-chain alkane), check if any carbon is bonded to four different groups; typically, in simple alkanes, carbons are bonded to hydrogens and carbons in a symmetrical way, so no chiral center is expected.
5. For the third and fourth compounds, similarly analyze the carbon atoms to see if any carbon has four different substituents, such as in the case of a carbon bonded to OH, CH3, H, and another carbon chain.