Chemical Names and Formulas SC2. Obtain, evaluate, and communicate information about the chemical and physical properties of matter resulting from the ability of atoms to form bonds. e. Ask questions about chemical names to identify patterns in IUPAC nomenclature in order to predict chemical names for ionic (binary and ternary), acidic, and inorganic covalent compounds. f. Develop and use bonding models to predict chemical formulas including ionic (binary and ternary), acidic, and inorganic covalent compounds.

Metals and Nonmetals Stairway of division on Periodic Table B, Si, Ge, As, Sb, and Te are metalloids Bi, Po, and At are disputed Elements to the RIGHT are nonmetals Elements to the LEFT are metals

Element or Compound? Elements include a single symbol Compounds include MORE THAN ONE symbol A formula is a representation of the atoms in a compound KCr2O7

Ionic Compounds Composed of cations and anions Formed from a metal (+) and non-metal (-), but can be all nonmetals* the ions are electrostatically attracted (ionically bonded)

Molecular Compounds Composed of neutral atoms the elements are usually nonmetals the atoms share electrons (covalently bonded)

Naming Compounds Your ability to name compounds and write formulas hinges on your ability to recognize whether a compound is ionic or molecular… So let’s see if you can do it –

IONIC or MOLECULAR? Be and S? P and F? C and N? Cs and Ag? Fe and Cl? Pb and I?

BASIC RULES for BINARY compounds First element is written/named 1st uses the full element name C  carbon K  potassium Second element is written/named 2nd uses the root of the name and ends in –ide chlorine  chloride oxygen  oxide

Here are all the prefixes… 1 – mono 6 – hexa 2 – di 7 – hepta 3 – tri 8 – octa 4 – tetra 9 – nona 5 – penta 10 – deca

Binary Molecular NAMING COMPOUNDS CCl4 N2O PF3 SiO2 H2O Use PREFIXES to indicate the number of atoms of each element Prefix is typically omitted on the first element if it is only one atom CCl4 N2O PF3 SiO2 H2O

Binary Molecular WRITING FORMULAS Use the compound name to write the formula with the correct symbols and the appropriate subscripts sulfur dioxide silicon tetrafluoride triphosphorus dioxide nitrogen trihydride dicarbon hexahydride

Ionic Charges Group 1  Group 2  Group 13  Group 14  1+ (often just +) 2+ 3+ 4+/-

Ionic Charges Group 15  Group 16  Group 17  Group 18  3- 2- 1- (often just -) No ion forms

Transition Metal Ion Charges Ag+ Cu+ and Cu2+ Zn2+ Hg2+ and Hg22+ Fe2+ and Fe3+ Co2+ and Co3+ Cr2+ and Cr3+ Mn2+ and Mn3+ Ni2+ and Ni3+

Transition Metal Ion Charges Pb2+ and Pb4+ Sn2+ and Sn4+

Binary Ionic NAMING COMPOUNDS If the first element has only one charge Use the standard naming rules KBr Ag3N AlCl3 Zn2C Mg3P2

Binary Ionic NAMING COMPOUNDS If the first element has variable charges Include a Roman numeral after the cation name to indicate which ion charge it has FeCl3 CuO Pb3N2 MnBr3 Sn2C

Na+ + Na+ + O2- = Na2O b/c 1+ + 1+ + 2- = 0 IMPORTANT! When an ionic compound is formed, the sum of the ion charges must equal ZERO Na+ + O2- ≠ NaO b/c 1+ + 2- = 1- Na+ + Na+ + O2- = Na2O b/c 1+ + 1+ + 2- = 0

Are you ready for the shortcut? The criss-cross method allows you to easily back-determine ionic charges… Al3+ O2- Al O 3 2

Let’s see if you’ve got it… Li and Br  Mg and Cl  K and N  Al and O 

Binary Ionic WRITING FORMULAS lithium fluoride strontium sulfide If the first element has only one charge lithium fluoride strontium sulfide barium nitride beryllium bromide aluminum oxide

Binary Ionic WRITING FORMULAS iron(III) nitride tin(IV) chloride If the first element has variable charge iron(III) nitride tin(IV) chloride nickel(III) sulfide mercury(II) fluoride copper(I) phosphide

Ternary Ionic Consist of more than 2 elements Include at least one polyatomic ion

Polyatomic Ions Consist of 2 or more nonmetals that, as a unit, have a charge Most commonly anions Exception is ammonium Typically end with –ate or –ite Exception is hydroxide

Polyatomic Ions NH4+ ammonium OH- hydroxide MnO4- permanganate CO32- carbonate

Polyatomic Ions NO3- nitrate NO2- nitrite SO42- sulfate SO32- sulfite PO43- phosphate PO33- phosphite

Polyatomic Ions ClO4- perchlorate ClO- hypochlorite ClO3- chlorate ClO2- chlorite ClO4- perchlorate ClO- hypochlorite

Polyatomic Ions CrO42- chromate Cr2O72- dichromate

Ternary Ionic NAMING COMPOUNDS KMnO4 Li2CO3 FePO4 NH4OH Pb(NO2)2 Follow the standard rules, naming the cation and anion appropriately KMnO4 Li2CO3 FePO4 NH4OH Pb(NO2)2

Ternary Ionic WRITING FORMULAS calcium carbonate aluminum phosphite Follow the standard rules, writing the cation and anion appropriately calcium carbonate aluminum phosphite zinc dichromate ammonium oxide tin(II) hypochlorite

Acid Nomenclature Acids all have hydrogen as the cation So they most often start with H Naming and writing formulas for acids all depend on the anion format

Acid Nomenclature If the anion ends with –ide, the name is hydro-(anion root)-ic acid HCl  hydrochloric acid H2S  hydrosulfuric acid HBr  hydrobromic acid

Acid Nomenclature If the anion ends with –ate, the name is (anion root)-ic acid HNO3  nitric acid H2CO3  carbonic acid H3PO4  phosphoric acid

Acid Nomenclature If the anion ends with –ite, the name is (anion root)-ous acid HNO2 nitrous acid H2SO3  sulfurous acid HClO2  chlorous acid