Which of the following structural formulae shows citric acid, also known as 2-hydroxypropane-1,2,3-tricarboxylic acid? (A) O O | || H2C---C---C---OH | | | OH O OH | | H H - HSC - SSCE Chemistry - Question 8 - 2013 - Paper 1

The correct structural formula for citric acid is the one presented in option (A). Citric acid has three carboxylic acid groups (-COOH) and one hydroxyl group (-OH) when represented in the structural formula. The configuration includes a central carbon atom to which the hydroxyl group (OH) is attached, and surrounding carbon atoms bonded to carboxylic groups and hydrogen atoms. It is essential to confirm that there are sufficient hydroxyl and carboxyl groups in the structure to classify it as citric acid.