Reaction of Sodium with Organic CompoundsLet's take a look at this question:To determine the moles of hydrogen evolved we need to know the 3 functional groups that will react with sodium metal. 1. Alcohols to form alkoxideROH + Na → RO-Na+ + 1/2 H2(g)2. Phenols to form phenoxidePhOH + Na → PhO-Na+ + 1/2 H2(g)3. Carboxylic acids to form carboxylateRCOOH + Na → RCOO-Na+ + 1/2 H2(g)All these functional groups undergo deprotonation or donate their proton. Hence the reaction with sodium is considered as acid-base or neutralisation with respect to organic compound. Here's my video lesson on how to compare acidity of these organic compounds. Finally we can now look back at citric acid. Citric acid contains 3 carboxylic acid groups and 1 alcohol group. For each of these functional groups, one mol of functional group will form 0.5 mol of H2 gas. Hence 1 mol citric acid will produce 2 mol H2(g). [Answer = B]Topic: Carboxylic Acid, Organic Chemistry, A Level Chemistry, SingaporeFound this A Level Chemistry video useful? Please LIKE this video and SHARE it with your friends! Join my 3000+ subscribers on my YouTube Channel for new A Level Chemistry video lessons every week. Check out other A Level Chemistry Video Lessons here! Need an experienced tutor to make Chemistry simpler for you?