Presentation on theme: "NAMING IONIC COMPOUNDS There are a few general rules that apply when naming ionic compounds. 1. Most ionic compounds are also called salts. 2. Most ionic."— Presentation transcript:
NAMING IONIC COMPOUNDS There are a few general rules that apply when naming ionic compounds. 1. Most ionic compounds are also called salts. 2. Most ionic compounds exist as solids and many dissolve to form aqueous solutions. 3. An ionic compound is made up of a metal and a nonmetal; metals are located on the left side of the periodic table and nonmetals are on the right side. 4. The cation (positive ion) is written first followed by the anion (negative ion). 5. Before naming compounds, you should first memorize the individual cations and anions.
Writing Chemical Formulas 1. The charge of the individual ions in a salt should add up to zero, the overall charge of the compound. For example NaCl is composed of Na+ ions and Cl- ions. For every one sodium ion you need one chloride ion (+1) + (-1) = 0 Ba 2+ and N 3- : You need 3 (+2 ) Barium ions to cancel out the 2 (-3) nitride ions so the overall charge of the compound is zero. 2. The individual ions should add up to the overall charge of the polyatomic ion. What is the charge of Mn in MnO 4 - ? 1 Mn + 4 O = -1 so 1(Mn) + 4 (-2) = -1 so Mn - 8 = -1 so Mn = +7
Nomenclature of binary ionic compounds Name the metal then the root of the nonmetal + ide ending: NaCl BaCl 2 NaF K2OK2OK2OK2O H2SH2SH2SH2S Mg 3 N 2 Sodium chloride Barium chloride Sodium fluoride Potassium oxide Hydrogen sulfideMagnesium nitride Notice that the cation is always mentioned first and then the anion. Notice that the anion always ends in -ide Notice that the number of elements in the compound is not mentioned in the name. Na 2 O K 2 S MgBr 2 AlN Ba 3 As 2 CaCl 2 AgCl AlH 3 ZnI 2 Li 3 P Name the following ionic compounds:
Nomenclature of binary ionic compounds Na 2 O = sodium oxide K 2 S = potassium sulfide MgBr 2 = magnesium bromide AlN = aluminum nitride Ba 3 As 2 = barium arsenide CaCl 2 = calcium chloride AgCl = silver chloride AlH 3 = aluminum hydride ZnI 2 = zinc iodideLi 3 P = lithium phosphide Answers:
Nomenclature of binary ionic compounds Some polyatomic anions: NO 3 - = nitrateNO 2 - = nitrite SO = sulfateSO 3 2- = sulfite PO 4 3- = phosphatePO 3 3- = phosphite CO 3 2- = carbonate HCO 3 1- = hydrogen carbonate or bicarbonate OH - = hydroxideCN - = cyanide C 2 H 3 O 2 - = acetateC 2 O 4 2- = oxalate
Nomenclature of binary ionic compounds NaHCO 3 K 2 SO 3 MgSO 4 KCN H 2 PO 4 Ca(OH) 2 NH 4 NO 3 Zn(NO 3 ) 2 Li 3 PO 4 HNO 3 Naming salts composed of the polyatomic ions is the same as with the monatomic anions. Metal name then polyatomic name. NaOH sodium hydroxide Ba(NO 3 ) 2 barium nitrate H 2 SO 4 hydrogen sulfate CsNO 2 cesium nitrite Sometimes there is a common name: KHCO 3 potassium hydrogen carbonate or potassium bicarbonate Note: the polyatomic anions must be memorized. Name the following ionic compounds:
Nomenclature of binary ionic compounds NaHCO 3 = sodium hydrogen carbonate or sodium bicarbonate K 2 SO 3 = potassium sulfite MgSO 4 = magnesium sulfate KCN = potassium cyanide H 2 PO 4 = hydrogen phosphate Ca(OH) 2 = calcium hydroxide NH 4 NO 3 = ammonium nitrate Zn(NO 3 ) 2 = zinc nitrate Li 3 PO 4 = lithium phosphate HNO 3 = hydrogen nitrate Answers:
Present NameSymbolFormer Name AntimonySbStibium CopperCuCuprum GoldAuAurum IronFeFerrum LeadPbPlumbum MercuryHgHydrargyrum PotassiumKKalium SilverAgArgentum SodiumNaNatrium TinSnStannum TungstenWWolfram Early Names of Elements
Nomenclature of binary ionic compounds CuHCO 3 FeSO 3 CuSO 4 Cr(CN) 3 Cr(PO 4 ) 2 Sn(OH) 2 W(NO 2 ) 5 Ti(CO 3 ) 2 CoPO 4 PbCl 2 The previous examples only named type 1 or “fixed oxidation state” cations. When naming type 2 or “variable oxidation state” cations the rules change. CuOH copper(I) hydroxide Fe(NO 3 ) 3 iron(III) nitrate CuSO 4 copper(II) sulfate Sn(NO 2 ) 4 tin(IV) nitrite Sometimes a common name exists: CuOH cuprous hydroxide Fe(NO 3 ) 3 ferric nitrate When naming type 2 cations, the systematic method (IUPAC) requires the use of roman numerals after the elemental name to represent the oxidation state of the cation. The common name uses the –ic ending for the higher oxidation state and –ous ending for the lower oxidation state. Many times the old latin or greek name is used as the root. Name the following ionic compounds:
PRACTICE PROBLEMS # 9a Below the formula, give the systematic name for the following compounds. If a common name exist, write it below the systematic name. 1. KBr 2. BaO3. Na 2 O 4. BiF 3 5. Cr 2 S 3 6. Ti(NO 3 ) 4 The problem set continues on the next page. potassium bromide Barium oxide Sodium oxide Bismuth (III) fluoride Chromium (III) sulfide Titanium (IV) nitrate or titanic nitrate
GROUP STUDY PROBLEM # 9a Below the formula, give the systematic name for the following compounds. If a common name exist, write it below the systematic name. 1. CaI 2 2. Cs 2 S 3. Al 2 S 3 4. CdI 2 5. SnCl 2 6. Zn(NO 3 ) 2 7. Fe 2 O 3 8. Fe(OH) 2 9. PbSO 4 The problem set continues on the next page.
PRACTICE PROBLEMS #9b Below the name, write the formula for the following compounds. Lithium chloride b) Aluminum sulfide e) Copper(II) oxide f) Iron(III) chloride i) Calcium bicarbonate l Potassium nitritePotassium perchlorate Ammonium carbonates s)Iron(II) phosphate w) Li + Cl - LiCl Al 3+ S 2- Al 2 S 3 CuO FeCl 3 Ca(HCO 3 ) 2 KNO 2 KClO 4 (NH 4 ) 2 CO 3 Fe 3 (PO 4 ) 2
GROUP STUDY PROBLEM #9b Below the name, write the formula for the following compounds. a) Barium oxide b) Sodium bromide c) Copper(I) oxided) Iron(II) chloride e) Potassium nitrite f) Calcium hydroxide g) Silver nitrate h) Ammonium chloride i) Lithium phosphate j) Sodium nitrite k) Sodium bicarbonate l) Calcium Carbonate m) Sodium sulfate n) Iron(III) hydroxide o) Copper(II) hypochlorite p) Sodium sulfite