Working backwards: name to formula Naming Compounds • It’s possible to determine a formula from a name • E.g. What is the formula of sodium oxide? • To get the answer, first write the valences: 1 2 Na O → Na2O • What is the formula of copper(II) oxide? 2 2 Cu O → Cu2O2 → CuO • For covalent compounds, simply use the prefixes to tell you the number of each element: • What is the formula for dinitrogen trioxide? N2O3 • Give formulae for: lithium sulfide, dinitrogen Day 2 monoxide, lead(IV) sulfate Assignment Naming Bases 1. Name each according to IUPAC rules: • Bases contain an OH group •CH O does not have an OH group a) ZnS, b) FeCl3, c) CaCO3, d) P2O5, e) NaCN, 6 12 6 • If an OH group is present it will be clearly f) N2F2, g) MgHPO4, h) Cu(BrO3)2, i) K2O, j) BF3 2. Give the valence of a) Fe in FeO, b) Mn in MnO indicated: e.g. NaOH, Ca(OH)2 2 • Also notice that bases have a metal (or positive 3. Write formulas for: a) sodium oxide, ion such as NH + at their beginning) b) potassium iodide, c) plumbic sulfide, 4 • Bases are named like other ionic compounds: d) mercury(I) oxide, e) ferrous oxide, • +ve is named first, followed by the polyatomic ion f) iron(II) phosphate, g) copper(II) fluoride, h) dichlorine monoxide, i) silver sulfide, Ca(OH)2 j) magnesium nitride, k) aluminum hypochlorite, CuOH l) iodine pentafluoride, m) calcium chromate, aluminum hydroxide n) diphosphorus pentasulfide ammonium hydroxide Naming Acids: Binary acids Naming Acids: Oxyacids • Naming does not depend on the state (aq) • All acids start with H (e.g. HCl, H2SO4) • 2 acids types exist: binary acids and oxyacids • 1) name the polyatomic ion Binary: H + non-metal. E.g. HCl 2) replace ate with ic, ite with ous Oxy: H + polyatomic ion. E.g. H2SO4 3) change non-metal root for pronunciation • Each have different naming rules. 4) add “acid” to the name Binary acids: naming depends on state of acid E.g. H2SO3 • If it’s not aqueous: hydrogen + non-metal 1) sulphite, 2) sulphous, HCl(g) = hydrogen chloride 3) sulphurous, 4) sulphurous acid • If it is aqueous: hydro + non-metal + ic acid HNO2 hypochlorous acid HCl(aq) = hydrochloric acid (aqueous hydrogen chloride) HBr(s) HI(aq) H3PO4(aq) carbonic acid H2S(aq) H2S(g) Assignment: give formula or name Hydrates a) chloric acid • Some compounds contain H2O in their struc- b) hydrosulfuric acid ture. These compounds are called hydrates. c) hydrobromic acid • This is different from (aq) because the H2O is d) phosphorous acid part of the molecule (not just surrounding it). e) iodic acid • The H2O can usually be removed if heated. • A dot separates water: e.g. CuSO •5H O is f) HCl(g) 4 2 copper(II) sulfate pentahydrate. g) HCl(aq) • A greek prefix indicates the # of H O groups. h) H SO (s) 2 2 4 Na SO •10H O i) H SO (aq) 2 4 2 2 4 NiSO •6H O j) HClO 4 2 2 sodium carbonate monohydrate k) HF(aq) barium chloride dihydrate .