1. Ch. 7 – Chemical Formulas & Chemical Compounds
This chapter introduces methods for naming, writing, and identifying chemical compounds.
Examples: CaCO3 – limestone, NaOH – lye, HCl – muriatic acid, NaCl – table salt, C6H12O6 – glucose, C12H22 O11 – sucrose.

2. Al2O3 – How many Al? How many O?
Al2(SO4)3 – How many Al,S, & O?
Monatomic ions form from a single atom
Ex. Na+, Cl -, Mg2+
Cation- positive
Anion – Negative
Binary compounds are composed of 2 different elements.
Ex. Sodium chloride, Barium sulfide

3. Naming Compounds New system of nomenclature (Stock System)
Write the 1st element’s name  usually positive
Write the 2nd element’s name – use the suffix –ide
If the 1st element is a transition element (3-12) or an element with more than one charge, you need to place a roman numeral behind it to show its charge.
Be able to recognize if some of the elements in the compounds are polyatomic ions.
EXAMPLES: KI, Sr2F, CuCl, ZnS, Fe2O3

4. Old System of Nomenclature
Instead of using roman numerals for elements with more than one charge, you use the following:
ous for the suffix of the element if it’s the lower charge.
ic for the suffix of the element if it’s the higher charge.

5. Nomenclature is the method of naming chemical compounds.
Oxyanions are polyatomic ions that contain oxygens
Ex. OH-, SO4-
Numerical Prefixes (Table 7-3) – pg. 212
Ex. 2 –di, 3 – tri, 4 – tetra, 5 - pent
Binary compounds with prefixes:
NO2 – nitrogen dioxide
N2O5 - ?

6. Binary Acids & Oxyacids
Binary acids are solutions of binary compounds with hydrogen at the beginning.
Ex. HCl, HF, HBr
Oxyacids contain H,O, and a third element.
Ex. HNO3, H2CO3, H2SO4, H3PO4