Unit 4 Chemical Formulas Ionic Molecular Cation (+) Anion (-) No ions All nonmetals metals nonmetals Ammonium compounds are ionic even though they contain only nonmetals NH4+1 Acids are molecular compounds that begin with the element H. This means they produce hydrogen ions in solution. H+ Bases are ionic compounds that end with hydroxide ions OH-1 Salts are ionic compounds that don’t have hydroxide

Location of metals and nonmetals Note: Hydrogen is a nonmetal Metals Nonmetals Metalloids

HCl NaNO3 CaCO3 CO2 FeCl3 O2 H3PO4 Mg(OH)2 molecular (Acid) ionic Hydrogen is a nonmetal Acids start with “H” Ionic compounds start with metals or ammonium, NH4+ . Bases have OH- anions molecular (Acid) HCl NaNO3 ionic (salt) ionic CaCO3 CO2 (salt) molecular ionic (salt) FeCl3 molecular O2 H3PO4 Mg(OH)2 molecular (Acid) ionic (base)

NH4Cl SO2 HNO3 NaCl KOH NO2 ionic (salt) molecular molecular (acid) Hydrogen is a nonmetal Acids start with “H” Ionic compounds start with metals or ammonium, NH4+ . Bases have OH- anions ionic (salt) NH4Cl SO2 molecular HNO3 NaCl molecular (acid) ionic (salt) KOH NO2 ionic (base) molecular

NAMING Chemical Formulas Ionic Molecular Cation (+) Anion (-) Monatomic anion ends in “ide” Transition metals with multiple charge use Roman numerals. (Reference sheet) CaCl2 calcium chloride CuCl2 copper (II) chloride Polyatomic ions (Use Reference sheet) KMnO4 potassium permanganate

Polyatomic ions Reference: ammonium, NH4+1 hydroxide, OH- nitrate, NO3-1 carbonate, CO32- -2 lithium chloride LiCl KNO3 potassium nitrate MgCO3 Na2O magnesium carbonate sodium oxide +6 -6 Fe3+ -2(3) Iron (III) oxide Fe2O3 Iron (II) oxide FeO NH4NO3 Mg(OH)2 ammonium nitrate magnesium hydroxide

Polyatomic ions Reference: ammonium, NH4+1 hydrogen carbonate, HCO31- (bicarbonate) dichromate, Cr2O72- sulfite, SO32- sulfate, SO42- phosphate, PO43- ammonium chloride NH4Cl CaCr2O7 calcium dichromate sodium hydrogen carbonate sodium bicarbonate NaHCO3 Ca3(PO4)2 calcium phosphate sodium sulfate Na2SO4 calcium sulfite CaSO3

NAMING Chemical Formulas Ionic Molecular Cation (+) Anion (-) mono 1 di 2 tri 3 tetra 4 penta 5 hexa 6 hepta 7 octa 8 nona 9 deca 10 Cation (+) Anion (-) All nonmetals Use prefixes Use periodic table and (Reference sheet) carbon monoxide CO carbon dioxide CO2 carbon tetrachloride CCl4 dinitrogen monoxide N2O

Naming Binary Molecular Compounds - Compounds between two nonmetals - First element in the formula is named first. - Second element is named as if it were an anion. - Use prefixes - Only use mono on second element - CO = carbon monoxide CO2 = carbon dioxide CCl4 = carbon tetrachloride N2O = dinitrogen monoxide

SO2 N2O4 NO2 P2O5 PCl3 PCl5 SF8 XeF4 NO OF2 AsCl3 NI3 sulfur dioxide mono 1 di 2 tri 3 tetra 4 penta 5 hexa 6 hepta 7 octa 8 nona 9 deca 10 dinitrogen tetraoxide N2O4 nitrogen dioxide NO2 P2O5 diphosphorus pentaoxide phosphorus trichloride PCl3 phosphorus pentachloride PCl5 sulfur octafluoride SF8 xenon tetrafluoride XeF4 nitrogen monoxide NO oxygen difluoride OF2 arsenic trichloride AsCl3 nitrogen triiodide NI3

Molecular Formulas (Acid Naming) Acids without oxygen: General formula HA where A = “anion” Hydro_______ic acid HF = Hydrofluoric acid HCl = Hydrochloric acid HBr = Hydrobromic acid HI = Hydroiodic acid HCN = Hydrocyanic acid CN- = cyanide anion

Naming Acids H+ + (anions with oxygen) Acids with oxygen: “ate-ic ite-ous” Anion name Acid name ____ate ____ic acid ___ite ___ous acid HNO3 = Nitr__?__ acid Anion NO3-1 = nitrate Nitric acid HNO2 = Nitr__?__ acid Anion NO2-1 = nitrite Nitrous acid

Naming Acids H+ + (anions with oxygen) Formula H+ with Anion Acid name H2SO4 2H+ + SO42- = sulfate Sulfuric acid H2SO3 2H+ + SO32- = sulfite Sulfurous acid HC2H3O2 H+ + C2H3O2-1 = Acetate Acetic acid H3PO4 3H+ + PO43- = Phosphate Phosphoric acid HClO4 H+ + ClO41- = Perchlorate Perchloric acid H2CO3 2H+ + CO32- = Carbonate Carbonic acid