When elements have more than one charge, it is important to distinguish which charge is being used. We will do this in the way we name the ion.

This tutorial explains how to use the stock naming system. The Stock system or Stock's system was designed by Alfred Stock German chemist , and first published in In , a German commission recommended Stock's system to be adopted with some changes. For example, FeCl2, which would have been named iron 2 -chloride according to Stock's original idea, became iron II chloride in the revised proposal.

Stock System Naming - Chemistry LibreTexts

In , Stock approved of the Roman numerals, but felt it better to keep the hyphen and drop the parenthesis. This suggestion has not been followed, but the Stock system remains in use worldwide.

How to Write a Formula for an Ionic Compound using the Stock Naming System. Write the formula for copper II chloride.

You may also find these related tutorials helpful. Compounds in Crust of Earth.

Elements in Crust of Earth. How To Round Numbers. Ionic Compounds Using the Stock Naming System. Write the symbol for the given cation name.

Ionic Compounds Using the Stock Naming System

Use the number in parenthesis as the cations charge. Remember, if you are using a polyatomic ion, DO NOT touch anything in the parenthesis. If you are using a polyatomic ion and there is no number outside of the parenthesis, you can remove the parenthesis.