2Metals, Nonmetals and Metalloids The stair-step line in the periodic table separates metals from nonmetals. Elements bordering this line are metalloids
3Formulas of ElementsFor most elements, the smallest independent particle is an atom.The formula of the element is the elemental symbol.Element FormulaHelium HeLithium Li
4Seven elements form stable diatomic molecules Formulas of ElementsSeven elements form stable diatomic molecules
5Compounds of Two Nonmetals Binary Molecular CompoundA compound formed by two nonmetalsor a metalloid and a nonmetal.
6Compounds of Two Nonmetals Naming Binary Molecular CompoundsThe first word is the name of the first element.A prefix is used to indicate the number of atoms.The second word is the name of the second element, changed to end in –ide.
7Compounds of Two Nonmetals Number prefixes used in chemical namesNumber Prefix Number Prefix1 mono hexa-2 di hepta-3 tri octa-4 tetra nona-5 penta deca-
8Compounds of Two Nonmetals Write the name of N2O5.N = nitrogen; 2 = diThe first word is dinitrogenO = oxygen, Change oxygen to end in -ide: oxide; 5 = pentaThe second word is pentoxide(the letter a in prefixes is omitted if the resulting word sounds better)dinitrogen pentoxide
9Compounds of Two Nonmetals Write the formula of nitrogen trifluoride.No prefix on the first word, so mono- is implied = 1 atom.The symbol of nitrogen is N.Tri- prefix on the second word = 3 atoms.-fluoride is an “-ide modified” fluorine = F.NF3
10Compounds of Two Nonmetals Two compounds are so common they are always called by their traditional names:H2O is waterNH3 is ammonia
11Ions, Cations, Anions Ion Charged particle formed when a neutral atom or molecule loses or gains electrons.CationPositively charged ion.AnionNegatively charged ion.
12Ions formed by One Element The charge on a main-group (U.S. A group) ioncorresponds to its group number:Group 1A 2A 3A 5A 6A 7ACharge – 2– 1–
14Ions Formed by One Element Name of a monatomic cationName of element,followed by the word ion.Name of a monatomic anionName of element changed to end in -ide,
15Ions Formed by One Element What is the formula of a sodium ion?Na+
16Ions Formed by One Element What are the name and formula of the ion formed from a chlorine atom?Cl–Change the name chlorine to end in –ide.Chloride ion
17Ions Formed by One Element Many transition elements (U.S. B groups) form multiple ions.The charge is shown bya Roman numeral enclosed in parentheses.Cr2+ is the chromium(II) ionCr3+ is the chromium(III) ion
18Ions Formed by One Element Some transition element ions always occur with only one chargeZn2+ is zinc ionAg+ is silver ionNi2+ nickel ionSpecial CaseHg22+ is called mercury(I) ion.
21H3O+ is called hydronium ion. Acids and Their AnionsAcidMolecular compound that reacts with water to produce a hydrated hydrogen ion and an anion.Ionization of hydrochloric acid HClH2O + HCl → H3O+ + Cl–H3O+ is called hydronium ion.
22The Acids of Chlorine and Their Anions Acids and Their AnionsThe Acids of Chlorine and Their Anions# of O atoms Acid prefix Anion prefixCompared with and/or suffix and/or suffix-ic acid and -ate anion (Example) (Example)One more per ic per- -ateHClO4 (perchloric) (perchlorate)Same ic ateHClO3 (chloric) (chlorate)One fewer ous iteHClO2 (chlorous) (chlorite)Two fewer hypo- -ous hypo- -iteHClO (hypochlorous) (hypochlorite)No oxygen hydro- -ic ideHCl (hydrochloric) (chloride)
23The names and formulas of following acids should be memorized Acids and Their AnionsThe names and formulas of following acids should be memorizedAcid Ionization Equation Ion NameChloric acid HClO H+ + ClO3– Chlorate ionNitric acid HNO H+ + NO3– Nitrate ionSulfuric acid H2SO H+ + SO42– Sulfate ionCarbonic acid H2CO H+ + CO32– Carbonate ionPhosphoric acid H3PO H+ + PO43– Phosphate ion
26Formulas of Ionic Compounds A compound made up of ions.The formula unit must have an equal number of positiveand negative charges.
27Formulas of Ionic Compounds Formula of the cation, followed by the formula of the anion. (omit the charges).Subscripts are used to show the number of each ion in the formula unit.(sum of charges must equal to zero)Omit the subscript if only one ion is needed.Enclose formula of the polyatomic ion in parentheses and place the subscript after the closing parentheses.
28Formulas of Ionic Compounds What is the formula of magnesium chloride?Magnesium is in Group 2A, so its ion is Mg2+.Chlorine is in Group 7A, so its ion is Cl–.Two 1– ions are needed to balance the 2+ ion.MgCl2.
29Formulas of Ionic Compounds What is the formula of barium nitrate?Barium cation is Ba2+Nitrate anion is NO3–Nitrate ion must be enclosed in parenthesesBa(NO3)2
30Memorize the following common and important ions: Other Acids and IonsMemorize the following common and important ions:Hydroxide ion OH–Ammonium ion NH4+
31Names of Ionic Compounds Example:Write the name of Zn(NO3)2.Solution:Zinc ion has only one common charge, 2+, so the magnitude of the charge is not included in its name: zinc ion.NO3– comes from the memorized acid HNO3, nitric acid.To name the ion, the -ic ending changes to -ate: nitrate ion.Zinc nitrate
32Names of Ionic Compounds How to Write the Name of an Ionic CompoundWrite the name of the cation.Write the name of the anion.
33Names of Ionic Compounds Write the name of CoCl2.There is more than one common charge for cobalt ions.We will have to use the anion to determine this charge.Chlorine is in Group 7A, so the charge on the ion is 1–: Cl–.The name of the anion is changed to end in -ide: chloride ion.Two 1– ions require a 2+ ion to balance the charge: cobalt(II) ion.Cobalt(II) chloride
34HydratesHydrateA solid compound that includes water molecules as part of its crystal structure.
35Water of crystallization HydratesWater of crystallizationWater molecules that are part ofthe crystal structure in a hydrate.Anhydrous compoundAn ionic compound without water.
36Hydrates Formulas of Hydrated Compounds Formula of ionic compound, followed by the number of water molecules, separated by a dot.Example:Copper (II) sulfate pentahydrateCuSO4 • 5 H2OThere are five water molecules forevery formula unit of copper (II) sulfate.
37Hydrates Names of Hydrated Compounds Use the prefixes for naming binary molecular compoundsto indicate the number of water molecules associatedwith each formula unit of the anhydrous compound.Example:MgSO4 • 7 H2OMagnesium sulfate heptahydrate
38HydratesExample:What is the formula of iron(III) sulfate nonahydrate?Solution:Iron(III) ion is Fe3+.Sulfuric acid is H2SO4, so sulfate ion is SO42–.Nona- is the prefix for 9.-hydrate refers to water of hydration, H2O.2 × 3+ balances 3 × 2–.Fe2(SO4)3 • 9 H2O
39Homework Homework for chapter 6: 3, 5, 9, 13,15, 19, 21, 23, 25, 33, 35, 39, 41,43, 45, 47, 49Fill the tables 6-13, 6-14, 6-15 and 6-16