Chemical X

Chemical X is a powerful, mutagenic chemical that gives people and animals superpowers and special abilities. Professor Utonium seems to own an unlimited supply of it in his lab. The chemical was an accidental extra ingredient in the Professor's concoction for perfect little girls thanks to an accident caused by Jojo, the Professor's monkey. This led to the creation of the Powerpuff Girls, and the explosion turned Jojo into Mojo Jojo. Since then the chemical has been used in numerous episodes, usually to give superpowers to people and animals. Mojo Jojo himself uses it to turn other primates evil and intelligent in his image, with oversized brains, green skin, pink eyes and the ability to speak. The chemical is also responsible for giving the Girls their distinctive appearance, as seen in "Oops, I Did It Again".

The Chemical's appearance is a viscous black liquid similar to oil, and is usually contained in a round glass bottle with a cork on it, though in the episodes "Mo Job" and "Twisted Sister" it appeared as glowing light blue liquid. It is also in a powder form, as seen in "Toast of the Town". Despite being an important plot point in some episodes, very little is actually known of the chemical itself, such as how it is made or whether or not it naturally occurs.