ELI5: Explain Like I'm 5

Pseudohalogen

A pseudohalogen is a group of non-metal elements that act like halogen elements. Halogen elements are a group of special elements like chlorine, fluorine, bromine, and iodine. Pseudohalogens act very much like halogen elements, but instead of being made of elements like chlorine, they are made up of other non-metal elements like sulfur, selenium, tellurium, and phosphorus. These pseudohalogens can do things like react with other elements to form bonds and make new compounds.