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. Thursday, November 29 Turn in Compound Naming Race sheet
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. Friday, November 30 Take out sheet of paper, title
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 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
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

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
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: amu
average mass of H2O molecule = 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 = 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 × 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 mass of H2O molecule = 18.02 g/mol
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 = 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 = 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 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 g/mol
Unknown: moles C13H18O2
molecules C13H18O2
total mass of C

22. Molar Mass Conversions
Sample Problem Solution
grams moles
moles molecules
moles C13H18O 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 = g