The chemist is found in his house in Rimmington. He will explain to players how to make oil lanterns and other light sources that require molten glass to make. He will also give you a sieve for making imp repellent. During Biohazard, he gives the player touch paper for Guidor. The chemist makes another appearance during the quest A Void Dance, where he helps analyse a sample you find.
A tasks icon appears over his house in the world map. He is the Falador Tasks taskmaster for completing the medium set.