Ch. 4 Notes---Nomenclature: Chemical Names & Formulas Ionic Compounds (“________”): – Name or formula starts with a _________ (or NH 4 +, ammonium). – Other quick ways to tell if the compound is ionic: formula uses parentheses Example: ________________ formula contains more than 2 elements (capital letters) Example: ________________ name uses Roman numerals Example: ________________ name ends in “-ate” or “ite”. Example: _________________ salts metal Ca(OH) 2 FeCrO 4 lead(II) chloride barium sulfate

Molecular Compounds (“____________”): – Name or formula starts with a ____________ (exception: NH 4 + ) – Other quick ways to tell if the compound is molecular: Name has prefixes and also ends in “-ide”. (It must have both!) Examples: _________________,_______________________ Naming Ionic Compounds Just use your ion sheet and find the names of the ions. cation name anion name Practice Problems: Name the following ionic compounds. a) NaC 2 H 3 O 2 b) (NH 4 ) 2 CO 3 c) Fe(OH) 3 d) PbSO 4 molecules nonmetal carbon dioxidedinitrogen pentoxide sodiumammonium iron acetatecarbonate hydroxide (III)lead sulfate (II)

Writing Formulas for Ionic Compounds Step 1-- Use your ion sheet and find the ions and their charges. Step 2-- “Cross the charges” if they don’t balance out. Step 3-- Use parentheses around polyatomic ion “chunks”. Practice Problems: Write the formula for each ionic compound. copper(II) bromide ____________________ aluminum nitrite _________________________ barium hydrogen carbonate ___________________________ Cu +2 Br -1 = CuBr 2 …(don’t show 1’s) Al +3 NO 2 -1 = Al(NO 2 ) 3 Ba +2 HCO 3 -1 = Ba(HCO 3 ) 2

Naming Molecular Compounds You do not use the ion sheet for molecules because no __________ are needed. They ______________ electrons instead of transferring them. Use ________________ to indicate the # and kind of atom in the compound. mono=1 di=2 tri=3 tetra=4 penta=5 hexa=6 hepta=7 octa=8 non=9 deca=10 Use the general format shown below… prefix-(except mono)-name the 1st element prefix-name the 2nd element ending with -ide Practice Problems: Name the following molecules. N 2 O 5 CO Cl 4 F 7 SO 3 charges share prefixes dinitrogen pentoxide carbon monoxide tetrachlorine heptafluoride sulfur trioxide

Writing Molecular Formulas The prefixes in the name tell you the # of atoms of each element there are. (Those become the _________________ in the formula!) Practice Problems: Write the formula for each molecule. nitrogen monoxide carbon tetrachloride diphosphorous pentoxide Acids All acids begin with the element ________________. General format: H(X), where “(X)” represents the ______________. There are 2 general types of acids: – If the name of “(X)” ends in –ite or –ate, then it is an _________ acid. – If the name of “(X)” ends in –ide, then it is a ____________ acid. The acids just contains ____ elements, hydrogen and a nonmetal. (There’s NO oxygen!) subscripts NO CCl 4 P2O5P2O5 hydrogen anion oxy- binary 2

Naming Oxy-Acids 1. If the name of “(X)” ends in –ate… (anion root)-ic acid 2. If the name of “(X) ends in –ite… (anion root)-ous acid Practice Problems: Name these acids. H 2 SO 4 H 3 PO 3 HNO 3 H 2 CO 3 HC 2 H 3 O 2 HClO 2 Naming Binary Acids If the name of “(X)” ends in –ide… hydro- (anion root)-ic acid Practice Problems: Name these acids. H 2 SHClHF sulfuric acid phosphorous acid nitric acid carbonic acid acetic acid chlorous acid hydrosulfuric acidhydrochloric acidhydrofluoric acid

Writing the Formulas for Acids FIRST  You must determine the formula for the anion, “(X)”. 1. If the acid’s name starts with “________” (and ends in “–ic”), the name of the anion used ends in “_______”. Therefore, it is a _________ acid. (There’s only hydrogen and one other nonmetal in the formula!) The subscript on the hydrogen equals the anion’s charge! Examples: hydrobromic acid = ________ hydroiodic acid = _______ hydrosulfuric acid = ________ hydro -ide binary HBr HI H2SH2S

2. If the acid’s name ends with “______” without the “hydro-” prefix, the name of the anion used ends in “_______”. Therefore, it is an ____ acid. The subscript on the hydrogen equals the anion’s charge! Examples: perchloric acid = __________ oxalic acid = ___________ 3. If the acid’s name ends with “______”, the name of the anion used ends in “_______”. (It’s is also an oxy-acid.) The subscript on the hydrogen equals the anion’s charge! Examples: hypochlorous acid = __________ nitrous acid = ____________ sulfurous acid = ____________ -ic -ate oxy- HClO 4 H2C2O4H2C2O4 -ous -ite HClO HNO 2 H 2 SO 3