Now you can translate Al2O3 into “aluminum oxide” and you can abbreviate “copper (II) chloride” as CuCl2. Chemists in laboratories around the world use the same language when it comes to chemicals. You now know how to communicate in the language that chemists use. In this topic, you learned that all elements want to achieve stability. Some elements in ionic compounds achieve stability by gaining or losing electrons to obtain the electron configuration of the nearest noble gas. Metals become stable by losing electrons and becoming a cation or positive ion. Nonmetals stabilize by gaining electrons and becoming an anion or negative ion. When you are writing chemical formulas, you need to remember a few things. The smallest particle of an ionic compound is a formula unit and represents the smallest whole number ratio of cations to anions. The sum of the negative charges must balance out the sum of the positive charges in order to have an electrically neutral compound.