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Name: Abby C.
Status: student
Age: 14
Location: N/A
Country: N/A
Date: 2000

How, when ,why are is the root change in naming different elemnts in a formula. For the second element in a binary you are to ad "ide", explain how, when, why is "ite" and "ate" added to the root?

These are some accidents of history, which if it were possible, most chemists would like to retract, because when the suffixes were applied to various substances the chemistry in many cases was not well understood. But we are stuck with them so here goes:

-ide usually means that the element is in its elemental anionic form. So we have chloride, bromide, ... , oxide, sulfide,..., nitride, phosphide... And there are no oxygens attached to the "-ide" element.

-ate usually means the element in to which the largest possible number of oxygen atoms are attached. So we have chlorate [ClO3^-1], sulfate, phosphate and so on. However, some elements were found that contained more oxygens than was first thought possible so the naming system had to be patched up the take into account. So we have PER-chlorate [ClO4^-1].

-ite refers to the oxygenated anion of an element that contains some intermediate number of oxygen atoms. So we have sulfite [SO3^-2] and chlorite [ClO2^-1], but then comes along [ClO^-1]. What to do? Invent a new prefix, so we get HYPOchlorite.

There are of course the corresponding -ic, and -ous acids, too!!

Vince Calder

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