Ch. 7 – Chemical Formulas & Chemical Compounds  This chapter introduces methods for naming, writing, and identifying chemical compounds.  Examples: CaCO 3 – limestone, NaOH – lye, HCl – muriatic acid, NaCl – table salt, C 6 H 12 O 6 – glucose, C 12 H 22 O 11 – sucrose.

AAl 2 O 3 – How many Al? How many O? AAl 2 (SO 4 ) 3 – How many Al,S, & O? MMonatomic ions form from a single atom Ex. Na +, Cl -, Mg 2+ CCation- positive AAnion – Negative BBinary compounds are composed of 2 different elements. Ex. Sodium chloride, Barium sulfide

Naming Compounds NNew system of nomenclature (Stock System) Write the 1 st element’s name  usually positive Write the 2 nd element’s name – use the suffix – ide If the 1 st 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, Sr 2 F, CuCl, ZnS, Fe 2 O 3

OOld System of Nomenclature Instead of using roman numerals for elements with more than one charge, you use the following: –o–ous for the suffix of the element if it’s the lower charge. –i–ic for the suffix of the element if it’s the higher charge. –P–Pg. 20

NNomenclature is the method of naming chemical compounds. OOxyanions are polyatomic ions that contain oxygens Ex. OH -, SO 4 - NNumerical Prefixes (Table 7-3) – pg. 212 Ex. 2 –di, 3 – tri, 4 – tetra, 5 - pent BBinary compounds with prefixes: NO 2 – nitrogen dioxide N 2 O 5 - ?

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. HNO 3, H 2 CO 3, H 2 SO 4, H 3 PO 4