Acid (Fallout 76)
An acid is typically a corrosive substance that, by definition, contains a higher concentration of positive hydrogen ions than negative hydroxide ions. This substance is used sparingly in the crafting of chems and explosives.
Shows up in inventory as waste acid. Can be turned into bulk acid. You can harvest it from Acid Pools or put Resource Collectors on those Pools for better results. Several types of bugs bugs have acidic glands and Yao Guai are a good source. There are a few Workshops that produce acid.
Mappalachia atlas of locations (hardpoints)