Wednesday, November 28

1. Wednesday, November 28 • 16-30 Compound Naming Problems: Questions? • 31-40 = Homework Tonight • Must complete sheet to retake Quiz 1 & 2 • Thursday= Polyatomic Ions (Quiz #1 Retake) • Friday= Acids (Quiz #2 Retake) • Take out Ch.7 ½ Packet from yesterday

2. Ch. 7 Test Next Thursday! Thursday, November 29 • Turn in Compound Naming Race sheet at Front if you intend to retake quiz • Friday= Acids (Quiz #2 Retake) • Take out sheet of paper, title “Polyatomic Ions (Quiz #1 Retake)” • YOU WILL NEED CALCULATOR TODAY!

3. Ch. 7 Test Next Thursday! Friday, November 30 • Take out sheet of paper, title “Acids (Quiz #2 Retake)” if you are retaking quiz 2 You will need Formula Mass notes and calculator today.

4. Nomenclature QUIZ 1 RETAKE • Write the ion name or formula that corresponds: • Chlorate • ClO3 -1 • OH -1 • Carbonate • ClO4 -1 • NO3 -1 • NO2 -1 • Sulfate • CN -1 • SO3 -2 • Write the compound name: • CaBr2 • Na2CO3 • Ca(OH)2 • Write the formula: • Magnesium Carbonate • Calcium Nitrite • Write the ion name or formula that corresponds: • NH4 +1 • SO4 -2 • Sulfite • AsO4 -3 • PO4 -3

5. Nomenclature QUIZ 2 RETAKE • Write the nomenclature: • H2SO4 • Chloric Acid • Hydroflouric Acid • CH3COOH • HClO2 • Carbonic Acid • Sulfuric Acid • H2SO3 • Nitric Acid • HCl • H3PO4 • H2CO3 • Write the formula name: • NaI • CaO • NaCl • Ca(OH)2 • SO3 Write the formula: • Sodium Fluoride • Potassium Sulfide • Iron (III) Oxide

6. Chemical Formulas and Compounds Using Chemical Formulas

7. Using Chemical Formulas • Chemical Formulas • A chemical formula indicates • the elements present in a compound • the relative number of atoms or ions of each element present in a compound • Chemical formulas also allow chemists to calculate a number of other characteristic values for a compound: • formula mass • molar mass • percentage composition

8. Using Chemical Formulas • Formula Masses • The formula mass of any molecule, formula unit, or ion is the sum of the average atomic masses of all atoms represented in its formula • formula mass of water, H2O • average atomic mass of H: 1.01 amu • average atomic mass of O: 16.00 amu • average mass of H2O molecule = 18.02 amu

9. Using Chemical Formulas • Formula Masses • The mass of any unit represented by a chemical formula (H2O, NaCl) can be referred to as the formula mass

10. Using Chemical Formulas • Formula Masses • Sample Problem • Find the formula mass of potassium chlorate, KClO3

11. Using Chemical Formulas • Formula Masses • Sample Problem Solution • The mass of a formula unit of KClO3 is found by adding the masses of one K atom, one Cl atom, and three O atoms formula mass of KClO3 = 122.55 amu

12. The MOLE • What is a mole? • What is a mole of apples? • What is a mole of carbon? • What is a mole of H2O?

13. Using Chemical Formulas • Molar Masses • The molar mass of a substance is equal to the mass in grams of one mole, or approximately 6.022 × 1023 particles, of the substance • The molar mass of a compound is calculated by adding the masses of the elements present in a mole of the molecules or formula units that make up the compound

14. Molar Masses • One mole of water molecules contains exactly two moles of H atoms and one mole of O atoms. The molar mass of water is calculated as follows • A compound’s molar mass is numerically equal to its formula mass • molar mass of H2O molecule = 18.02 g/mol

15. Using Chemical Formulas • Formula Masses • Sample Problem • What is the molar mass of barium nitrate, Ba(NO3)2

16. Using Chemical Formulas • Formula Masses • Sample Problem Solution • One mole of barium nitrate, contains one mole of Ba, two moles of N (1 × 2), and six moles of O (3 × 2) molar mass of Ba(NO3)2 = 261.35 g/mol

17. Using Chemical Formulas • Molar Mass Conversions

18. Molar Mass Conversions • Sample Problem • What is the mass in grams of 2.50 mol of oxygen gas (O2)

19. Using Chemical Formulas • Molar Mass Conversions • Sample Problem Solution • Given: 2.50 mol O2 • Unknown: mass of O2 in grams moles O2 grams O2 amount of O2 (mol) × molar mass of O2 (g/mol) = mass of O2 (g) O2

20. Using Chemical Formulas • Molar Mass Conversions • Sample Problem • Ibuprofen, C13H18O2, is the active ingredient in many nonprescription pain relievers. Its molar mass is 206.31 g/mol • If the tablets in a bottle contain a total of 33g of ibuprofen, how many moles of ibuprofen are in the bottle? • How many molecules of ibuprofen are in the bottle? • What is the total mass in grams of carbon in 33g of ibuprofen?

21. Molar Mass Conversions • Sample Problem Solution • Given: 33g of C13H18O2, molar mass 206.31 g/mol • Unknown: moles C13H18O2 molecules C13H18O2 total mass of C

22. Molar Mass Conversions • Sample Problem Solution grams moles moles molecules moles C13H18O2 moles C grams C

23. Using Chemical Formulas • Molar Mass Conversions • Sample Problem Solution

24. Percentage Composition • It is often useful to know the percentage by mass of a particular element in a chemical compound • To find the mass percentage of an element in a compound, the following equation can be used: • The mass percentage of an element in a compound is the same regardless of the sample’s size

25. Percentage Composition • The percentage of an element in a compound can be calculated by determining how many grams of the element are present in one mole of the compound • The percentage by mass of each element in a compound is known as the percentage composition of the compound

26. Using Chemical Formulas • Molar Mass Conversions • Sample Problem • Find the percentage composition of copper(I) sulfide, Cu2S

27. Using Chemical Formulas • Molar Mass Conversions • Sample Problem Solution • Given: formula, Cu2S • Unknown: percentage composition of Cu2S formula molar mass mass percentage of each element

28. Molar Mass Conversions copper(I) sulfide, Cu2S • Sample Problem Solution Molar mass of Cu2S = 159.2 g