If you are using it for one of your Boy Scout requirements, see your handbook for a list of things you can teach. For most recent ILSC, our leader used making a paper airplane to demonstrate the EDGE method. What you teach should fit your audience and any requirement you are trying to fulfill. Reply.
Uses of Thallium. Thallium sulfate, which is odorless and colorless, was used as a rat poison and as an insecticide. This use has been discontinued in some countries, including the USA. Thallium sulfide is used in photocells because its electrical conductivity increases on exposure to infrared light.
Thallium is extremely soft, malleable and sectile enough to be cut with a knife at room temperature. It has a metallic luster that, when exposed to air, quickly tarnishes to a bluish-gray tinge, resembling lead. It may be preserved by immersion in oil. A heavy layer of oxide builds up on thallium if left in air.