Stock System-New Naming System Some metal elements can form two or more cations with a different charge. The stock system denotes the specific ion by putting the charge in ( ). Example: Iron (II) has a + 2 charge Iron (III) has a +3 charge

Other common examples Lead (II) has a +2 charge Lead (IV) has a +4 charge Tin (II) has a + 2 charge Tin (IV) has a +4 charge Copper (I) has a +1 charge Copper (II) has a +2 charge

Old Nomenclature-Don’t have to memorize these Copper (I) – cuprous Copper (II) – cupric Iron (II) – ferrous Iron (III) – ferric Tin (II) – stannous Tin (IV) – stannic Lead (II) – plumbous Lead (IV) – plumbic

Naming ionic compounds Nomenclature-naming system Positive ions is first, then negative ion Ex: sodium chloride NaCl

Practice Write formulas for the following: Copper (II) Sulfate CuSO4 Iron (III) oxide Fe2O3 Zinc (II) sulfide ZnS Vandium (IV) chloride VCl4 Cobalt (III) Nitrite Co(NO3)3

Practice http://www.quia.com/jg/65800.html -

Compounds containing Polyatomic ions Treat the polyatomic ion as a single atom Always put polyatomic ion in parentheses if there is more than 1 of them Example: ammonium chloride NH4Cl Practice Barium Nitrate Ba(NO3)2 FeSO4 iron (II) sulfate

Naming Molecular Compounds Old way of naming Molecular Compounds requires the Use of prefixes. (memorize These) 1 = mono 2 = di 3 = tri 4 = tetra 5 = penta 6 = hexa 7 = hepta 8 = octa 9 = nona 10 = deca

Naming Binary Molecular Compounds: Compounds with 2 elements The least EN Atom goes first C,P,N,H,S,I,Br,Cl,O,F The element is given a prefix if it contributes more than one element to the molecule. The second element: Combine a prefix with the root of that element with -ide at the end. Dioxide, pentoxide This is true for most molecules containing 2 elements The o or a at the end of a prefix is usually dropped when the name of the element begins with a vowel

Practice CO Carbon Monoxide CO2 Carbon Dioxide CCl4 Carbon TetraChloride SiF4- Silicon Tetraflouride Nitrogen Monoxide NO N2O3 Dinitrogen Trioxide Phosphorus Trichloride PCl3

Acids Oxyacid-Acids that contain hydrogen, Oxygen and another atom (usually a non-metal) H3PO4: Phosphoric Acid HNO2: Nitrous Acid Usually made from polyatomic ions and the addition of enough Hydrogens to balance out the ion.

Acids Naming: Practice HNO2 Sulfuric Acid Decide which polyatomic Ion is being used and use that rootword Polyatomic ions that end in ate  ic ite  ous Rootword(ic or ous) and Add Acid Practice HNO2 Nitrous Acid Sulfuric Acid H2SO4

Acids Binary Acids-Acids that consist of 2 elements: usually Hydrogen and one of the Halogens (there are others) HCl: Hydrochloric Acid HF: Hydroflouric Acid Naming: Hydro goes first Add the name of the second atom with ic at the end H2S Hydrosulfuric Acid Hydrobromic Acid HBr

Acids-Practice HI CH3COOH Sufurous Acid Carbonic Acid H2CO3 Hydroiodic Acid CH3COOH Acetic Acid Sufurous Acid H2SO3 Carbonic Acid H2CO3

Using Chemical Formulas Subscript indicates how many moles of that atom or polyatomic ion are in 1 mole of that compound. KNO3 Na2SO4 Ca(OH)2 (NH4)2SO3

Using Chemical Formulas Formula mass-sum of all the average atomic masses of all elements in compound. Ex: H2SO4 2 Hydrogen 2 x 1.01 = 2.02 1 Sulfur 1 x 32.07 =32.07 4 Oxygen 4 x 16.00 =64.00 total = 98.09 OR EX: NaCl 1 sodium ion 22.99 1 Chloride ion 35.45 total= 58.44

Practice (NH4)3(PO4) Al2O3 Na2O

Molar Mass as a Conversion Factor Converting between moles and grams with compounds. 1st calculate formula mass of given compound. (unit gram/mole) 2nd convert either by multiplying or dividing by the formula mass molesgrams (x) by formula mass Gramsmoles (divide) formula mass

Practice What is the mass of 4.5 moles of Ca(CO3)? 4.5 x 102 g Ca(CO3) What is the mass of 2.0 moles of Na(NO3)? 1.7 x 102 g Na(NO3) How many moles are contained in 25.0 grams of AgCl? .174 mol AgCl How many moles are contained in 5.0 grams of ZnCl2? .037 mol ZnCl2

Percent Composition Gives the percent by molar mass of each element in a compound. 1st calculate the total molar mass of the compound H2SO4 2 H x 1.01 = 2.02 1 S x 32.07 = 32.07 4 O x 16.00 = 64.00 98.09

continued 2nd Divide each individual atoms mass by the total mass. 3rd Multiply each by 100 (or move decimal two places to the right) 2 H x 1.01 = 2.01/98.16 = 0.0205 =2.05% 1 S x 32.07 = 32.07/98.16 = 0.327 =32.7% 4 O x 16.00 = 64.00/98.16 = 0.652 =65.2% Check to make sure % adds to 100 (or close to 100) More Practice Pg 244 Practice Problems ZnSO4•7H2O 42.85%

Determining Chemical Formulas Empirical formula-symbols of elements in compound showing the smallest whole number ratio. Convert percents of elements in a compound into formula.

How to: 1st change % to grams 2nd convert grams to moles 3rd divide each by the least Ex: Determine the formula of a compound made up of the following percents: 32.38 % Na 22.65 % S 44.99 % O

Practice problems 1-3 p.247

Molecular formulas Actual formula of a molecular compound C2H4 simplifies to CH2 C3H6 simplifies to CH2 C2H4 (ethene) and C3H6 (cyclopropane)

How the empirical formula relates to the molecular formula: EF = empirical formula MF = molecular formula X( EF) = (MF) 1st solve for x X= (MF)/(EF) HINT-BIG NUMBER ALWAYS GOES ON TOP Multiply (EF) by x to get the molecular formula

Example The empirical formula of a cpd of phosphorus and oxygen was found to be P2O5. the molar mass of this cpd is 283.89g/mol. What is the cpd’s molecular formula?

Practice Problems 1-2 p. 249

Give the formula for the following: 1. potassium oxide 2. lithium phosphide 3. aluminum chloride 4. calcium bromide 5. iron(II)oxide 6. iron(III)oxide 7. tin(IV)fluoride 8. copper(II)chloride 9. lead (II) sulfide 10. magnesium chloride

Determine the molecular formula: 1. Emperical formual = CH, molar mass = 78 g/mole 2. Emperical formula = NO2, molar mass = 92.02 g/mol 3. Mesitylene has an empirical formula of C3H4. What is the molecular formula(mass 121)?