In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.
Q: Reacting this compound with hydrogen sulfide creates trithiane, while its suspended in an 18M solution of sulfuric acid in the reagent used to test for MDMA, called the Marquis reagent. A 10% Neutral Buffered solution of this compound is used as a histological fixative, and during immunoprecipitation assays its used to crosslink proteins. In solution it polymerizes to either its "para" form or trioxane, which is why its stored as a 37% solution. The Cannizzaro reaction of this compound creates methanol and methanoic acid. For 10 points, name this simple carbonyl compound, which is used to preserve cadavers and frogs.
A:
Science