 Common names can be confusing when naming compounds  Inaccurate and provides no hint of elements present

 writing chalk (calcium sulfate)

 Antacids (calcium carbonate) – also in sea shells, snail shells, eggshells

 Chemical formula – identifies which elements, and how much of each are in the compound

 Ion notation – element symbol with a superscript and a + or – sign at the top right  Some metals are able to form more than one type of ion (have more than one charge)  A Roman number is included in the ion name to show the ion charge  (I) = 1  (II) = 2  (III) = 3  (IV) = 4

 Name of non-metal changes to ‘ ide ’ at the end

 Rules  1) Name the metal ion first (simply the element name).  **If an element can form more than one kind of ion, include the Roman number to indicate the charge.  2) Name the non-metal second. Change the ending to ‘ide’.  **subscripts (small #) are ignored for naming compounds

 For elements that can make more than one ion  You can find the Roman # to use by using the subscripts in the formula  This is written in the middle of the compound name