Mercury (element)

Mercury is a substance which is one of the only metals that is liquid at room temperature and is poisonous. Different types of mercury have different levels of toxicity, for example, elemental mercury is generally safe to handle, even with bare hands, as long as you wash your hands after, however this is not recommended as it can penetrate your skin and cause poisoning. It also produces fumes which are dangerous to breath in, so it is recommended that you use a fume hood or use it outside. Elemental mercury has a silvery appearance. On the other end of the spectrum, Dimethylmercury is extremely dangerous, as it can penetrate many types of gloves within seconds, and just a few drops on your hand is enough to cause lethal mercury poisoning.