Lithium, beryllium and boron are the elements that have an oxidation number of +3.
Oxidation number refers to the total number of electrons that an atom gains or loses in order to get stability and formed chemical bond with another atom. Atoms that lose electron form positive charge.
So we can conclude that Lithium, beryllium and boron are the elements that have an oxidation number of +3.
Learn more about oxidation here: https://brainly.com/question/25886015
#SPJ2
