Soldering terminology

Compounds containing halogens, i.e. elements of the group 17 in the periodic table (F, C, Br, I, At), namely fluorides, chlorides, bromides, iodides and astatides. The first three are often used as activators for flux. Compounds between halogens are called inter halogens while compounds between halides and themselves or other halogens are known as polyhalides. Polyhalides are represented with formulas such as MXn, MxmYn or MXlYmZn where X, Y and Z are different halogens and M is an alkaline metal or ammonium, etc.