Plot: What do the smells of feet, armpits, vomit, and goats all have in common? (Besides being super gross…) Carboxylic acids! Despite being responsible for some of our least favorite odors, carboxylic acids are also super useful in organic chemistry. In this episode of Crash Course Organic Chemistry, we’ll review carboxylic acid synthesis and nomenclature, react carboxylic acids to form salts, esters, and acid chlorides, and start our journey towards synthesizing one of the most important organic chemicals in medicine, penicillin!