See image — IUPAC and Nomenclature Chemistry Question

💡 Solution & Explanation

Concept: IUPAC nomenclature of hydroxy acids requires identifying the longest carbon chain containing the carboxylic acid group, numbering from the carboxyl carbon (C-1), and specifying the position of the hydroxyl substituent. Step 1: Identify the structure. The compound is CH3—CH(OH)—COOH (the dot above CH in the image indicates a substituent, which by context and the answer choices is an OH group, making this lactic acid). Step 2: Count the carbon chain. There are 3 carbons: C1 (COOH), C2 (CH-OH), C3 (CH3). The parent chain is propanoic acid (3 carbons with terminal -COOH). Step 3: Number the chain. The carboxyl carbon is C-1 by IUPAC convention. The OH group is on C-2. Step 4: Name the compound. The OH group at position 2 on propanoic acid gives: 2-Hydroxypropanoic acid. Why other options fail: - (b) 1-Hydroxypropanoic acid: C-1 is the carboxyl carbon itself; OH cannot be placed there separately. - (c) 1-Hydroxyethane carboxylic acid: This is a non-standard/trivial-style name and incorrect IUPAC format. - (d) 1-Hydroxyethanoic acid: Ethanoic acid has only 2 carbons; the compound has 3 carbons, so ethanoic is wrong. Therefore, the correct answer is A.