Chem 1ALecture 4HomeworkRead chapter 2 ALEKS homework: XM4NG-QNDN6Chapter 2 book problems• Symbolic Representation• Ions• Periodic Table• Common IonsRecapMolecules – are assemblies of two or more atoms tightly bound together. This “package” of atoms behaves like a single distinct object. Pure substance.O2 v O3Dioxygen Ozonediatomic triatomicodorless pungent smellgas – colorless gas – pale bluemp/bp = 54.36 K / 90.20 K mp/bp = 80.7 K / 161.3 Kmuch more reactive MoleculesEmpirical (or simplest) formula – gives only the relative number of atoms of each type in a molecule.Molecular formula – the actual numbers and types of atom in a moleculeNameEmpiricalMolecularWaterH2OH2OPeroxideHOH2O2EthanolC2H6OC2H6ODimethylEtherC2H6OC2H6OFormulaIonic Compounds - are compounds that contain positively charged ions and negatively charged ions.Na  Na+ + e-Cl + e- Cl-Na++ Cl- NaClMetals + Nonmetals  Ionic CompoundsCa  Ca2++ 2e-F + e- F-Ca2++ F- CaF2 Ionic CompoundsIons Formula a) K and Clb) Ca and Oc) Ca and ClK+Cl–KClCa2+O2–CaOCa2+Cl–CaCl2Predict Molecular formula:a) Kr b) Se c) Sr d) Rbe) I am lostAn element’s most stable ion forms an ionic compound XCl2. If the ion of element X has 36 electrons, what is the identity of the element?a) Kr b) Se c) Sr d) Rbe) I am lostAn element’s most stable ion forms an ionic compound XCl2. If the ion of element X has 36 electrons, what is the identity of the element?Polyatomic Ion - is a charged compound composed of two or more atoms bonded together. Polyatomic Ions• Monatomic cations take the name of the element itself:Na+- sodium ion Ca2+- calcium ion Al3+- aluminum ion• For metals that can form different charges, the positive charge is given by a Roman numeral in parentheses following the name of the metal.Fe 2+- iron(II) ion Cu+- copper(I) ionFe3+- iron(III) ion Cu2+- copper(II) ion Positive Ions• Older method use the –ous or –ic, representing the lower and higher charged ions, respectively .Fe 2+- ferrous ion Cu+- cuprous ionFe3+- ferric ion Cu2+- cupric ion•Non-metals have names that end in –ium.NH4+- ammonium ionH3O+- hydronium ionPositive Ions• Monatomic anions have names formed by dropping the ending of the name of the element and adding the ending –ide.H-- hydride ion O2-- oxide ion N3-- nitride ionHalogens – are common negative ions• Polyatomic anions containing oxygen have names ending in –ate or -ite.NO3-- nitrate ion SO42-- sulfate ionNO2-- nitrite ion SO32-- sulfite ionNegative IonsIf there are more than two ions in the series, then the prefixes hypo-, meaning “less than,” and per-,meaning “more than,” are used. ClO− hypochlorite BrO− hypobromite IO− hypoioditeClO2−chlorite BrO2− bromite IO2−ioditeClO3− chlorate BrO3− bromate IO3−iodateClO4− perchlorate BrO4−perbromate IO4−periodateWhen naming these ions in the homework, be sure to include the word ion in your answer, as in “perchlorate ion.”Negative IonsNames of ionic compounds are the cation name followed by the name of anion.Al(NO3)3 aluminum nitrate CuI  copper(I) iodide CuI2 copper(II) iodideNaCl  sodium chlorideCaF2 calcium flourideNomenclatureUsually a non-metal + non-metal• Leftmost (based on periodic table) element is usually written first.• If in the same group, the lowest is named first.• The name of the second element is give an –ide ending.• Greek prefixes (mono, di, tri, tetra…) are used to indicate the number of each atom. Mono is never used on the first element.N2O4dinitrogen tetroxideNF3nitrogen trifluorideP4S10tetraphosphorus decasulfideMolecular compoundsa) potassium phosphate, K3PO4b) iron(II) oxide, FeOc) calcium carbonate, CaCO3d) sodium sulfide, NaSe) lithium nitrate, LiNO3Which is not the correct chemical formula for the compound named?a) potassium phosphate, K3PO4b) iron(II) oxide, FeOc) calcium carbonate, CaCO3d) sodium sulfide, NaSe) lithium nitrate, LiNO3Which is not the correct chemical formula for the compound named?AcidsBinary acids are composed of hydrogen and a nonmetal. The names for binary acids have the following form:• HCl(aq) is hydrochloric acid. • HBr(aq) is hydrobromic acid.• HCl(g) refers to hydrogen chloride molecules in the gas phase, and not to the acid.AcidsThe names of acids containing oxyanions ending with -ite take this form: The names of acids containing oxyanions ending with -ate take this form:1) Name HNO3 Ions: H+and NO3–Name of anion: NO3–nitratereplace the ending –ate with –ic followed by acid Name of acid: HNO3 nitric acid2) Name HNO2 Ions: H+and NO2–Name of anion: NO2–nitritereplace the ending –ite with –ous followed by acid Name of acid: HNO2 nitrous acidNaming OxoacidsThe name of the compound NH4ClO4isA. ammonium chloride. B. ammonium chlorite.C. ammonium hypochlorite.D. ammonium chlorate.E. ammonium perchlorate.The name of the compound NH4ClO4isA. ammonium chloride. B. ammonium chlorite.C. ammonium hypochlorite.D. ammonium chlorate.E. ammonium perchlorate.A. phosphorus iodide.B. monophosphorustriiodide.C. phosphorus triiodide.D. phosphorus(III) iodide.E. potassium iodide.The name of the compound PI3 isA. phosphorus iodide.B. monophosphorustriiodide.C. phosphorus triiodide.D. phosphorus(III) iodide.E. potassium iodide.The name of the compound PI3 isA. cyanic acid. B. hydrogen cyanide.C. percyanic acid.D. hydrocyanic acid.E. hypocyanous acid.The name of the compound HCN(aq) isA. cyanic acid. B. hydrogen cyanide.C. percyanic acid.D. hydrocyanic acid.E. hypocyanous acid.The name of the compound HCN(aq) isA. HClOB. HClO2C. HClO3D. HClO4E. HClO5Which is the correct formula for chloricacid?A. HClOB. HClO2C. HClO3D. HClO4E. HClO5Which is the correct formula for