What is a thiol?

What is a thiol?

• A. A sulfur-containing organic compound with -SH group.
• B. The R-S-H functional group.
• C. An aromatic ring.
• D. A carbonyl group.

Answer: (B)

Remember that what defines a thiol is the sulfhydryl group, -SH, attached to a carbon framework. The standard way to express this is as R-S-H, where R is an alkyl or aryl group. This sulfhydryl group is the feature that sets thiols apart and governs their chemistry, including acidity and hydrogen-bonding tendencies. That’s why the precise description is the R-S-H functional group—the actual structural feature that defines a thiol. The other options point to different features (an aromatic ring or a carbonyl group) or describe a molecule that merely contains -SH without naming the specific functional group, which is less precise for defining what a thiol is.

Remember that what defines a thiol is the sulfhydryl group, -SH, attached to a carbon framework. The standard way to express this is as R-S-H, where R is an alkyl or aryl group. This sulfhydryl group is the feature that sets thiols apart and governs their chemistry, including acidity and hydrogen-bonding tendencies. That’s why the precise description is the R-S-H functional group—the actual structural feature that defines a thiol. The other options point to different features (an aromatic ring or a carbonyl group) or describe a molecule that merely contains -SH without naming the specific functional group, which is less precise for defining what a thiol is.