ACTIVITY
NAME THAT
COMPOUND
1
Minute to Name It!
A list of chemical formula and names
would be shown on the screen.
 Each student would need to identify the
corresponding name (if a formula is given)
or formula (if a name is given).

2
Li2Se
AlCl3
Sr3P2
BaI2
Mg2N2
KF
CaC2
MgH2
BeCl2
Cd3P2
CsCl
NaBr
BeCl2
Al2O3
BaS
Ferric oxide
Ferrous oxide
Chromium(II) sulfide
Chromium(III) oxide
Lead(IV) oxide
Copper(II) telluride
Mercury(II) oxide
Stannic fluoride
Plumbous bromide
Copper(I) chloride
Cobalt(II) fluoride
Lead(IV) oxide
Nickel(II) phosphide
Lead(IV) sulfide
Nickel(II) iodide
Li2Se
Lithium selenide
Fe2O3
Ferric oxide
AlCl3
Sr3P2
BaI2
Mg3N2
KF
CaC2
MgH2
BeCl2
Cd3P2
CsCl
NaBr
BeCl2
Al2O3
BaS
Aluminum chloride
Strontium phosphide
Barium iodide
Magnesium nitride
Potassium fluoride
Calcium carbide
Magnesium hydride
Beryllium chloride
Cadmium phosphide
Cesium chloride
Sodium bromide
Beryllium chloride
Aluminum oxide
Barium sulfide
FeO
CrS
Cr2O3
PbO2
CuTe
HgO
SnF4
PbBr2
CuCl
CoF2
PbO2
Ni3P2
PbS2
NiI2
Ferrous oxide
Chromium(II) sulfide
Chromium(III) oxide
Lead(IV) oxide
Copper(II) telluride
Mercury(II) oxide
Stannic fluoride
Plumbous bromide
Copper(I) chloride
Cobalt(II) fluoride
Lead(IV) oxide
Nickel(II) phosphide
Lead(IV) sulfide
Nickel(II) iodide
Stoichiometry of Formulas and
Equations
CHAPTER 3
Burning Magnesium
Chemical reaction:


2 Mg(s) + O2(g)  2 MgO(s)
48 amu
32 amu
80 amu
How do we look at this in terms of mass?

? grams
7
? grams
? grams
Mole (abbreviated mol)
SI unit for amount of substance
Number of entities as there are atoms in exactly 12 g of
12C
Equal to 6.022 x 1023 entities




8
Called the Avogadro’s number
How big is Avogadro’s Number?
Volume of world’s
oceans (L)
Age of the
earth (s)
World
population
Avogadro’s Number: 602,200,000,000,000,000,000,000
Distance from
earth to sun (cm)

9
College
tuition
Spreading 1 mole of marbles over the entire surface of the earth
would produce a blanket of marbles almost 5 km high.
A mole of water
10
A mole of other substances
O2 (g)
32.00 g
H2O (l)
18.02 g
CaCO3
100.09 g
Cu (s)
63.55 g
11
1 mole of Fe vs 1 mole of S
1 mole Fe
6.022 x 1023 Fe atoms
55.85 g Fe

12
1 mole S
6.022 x 1023 S atoms
32.07 g S
The mole allows us to count out exactly the same
number of things but use mass to do it!
Molecular Mass and Molar Mass

The molecular mass (or molecular weight) is the sum of the
atomic masses (in amu) in a single molecule.

The molar mass of a covalent compound is numerically equal
to the molecular mass, but in grams per mole.
13
Formula Mass and Molar Mass

The formula mass (or formula weight) is the sum of the
atomic masses (in amu) in a formula unit.

The molar mass of an ionic compound is numerically equal
to the formula mass, but in grams per mole.
14
Summary of Different Mass Terms
Term
Definition
Unit
Isotopic Mass
Mass of an isotope of an
element
amu
Atomic Mass
(aka Atomic Weight)
Weighted average mass of an
element’s naturally occurring
isotopes
amu
Molecular or
Formula Mass
(aka Molecular or
Formula Weight)
Sum of the atomic masses of
the atoms (or ions) in a
molecule (or formula unit)
amu
Molar Mass
Mass of 1 mole of a chemical
grams per
entity (e.g. atoms, ions,
mole (g/mol)
molecules, or formula units)
15
Practice Problem

What is the molecular mass of glucose (C6H12O6)?

Molecular Mass:

16
6 x 12.011 + 12 x 1.007 + 6 x 15.99 = 180.16 amu
Practice Problem

Complete the table below for glucose (C6H12O6,
MW = 180.16 g/mol)
Carbon
Hydrogen
Oxygen
Atoms in 1
glucose molecule
6
12
6
Mass C/H/O in 1
glucose molecule
6 x 12.01 =
72.06 amu
12 x 1.008 =
12.10 amu
6 x 15.99 =
96.00 amu
Atoms per mole
of compound
Moles of atoms
in 1 mole cmpd
Mass per 1 mole
of compound
17
6 (6.022x1023) 12 (6.022x1023)
atoms
atoms
6 moles of
12 moles of
atoms
atoms
72.06 g
12.10 g
6 (6.022x1023)
atoms
6 moles of
atoms
96.00 g
What’s in a Chemical Formula?
Al2(SO4)3 (s)









18
2 atoms of Al and 3 molecules of (SO4)21 formula unit of Al2(SO4)3 = 342.17 amu
1 mole Al2(SO4)3 = 342.17 g Al2(SO4)3
1 mole Al2(SO4)3 = 6.022 x 1023 formula units Al2(SO4)3
1 mole Al2(SO4)3 = 2 moles Al3+ ions
1 mole Al2(SO4)3 = 3 moles (SO4)2- ions
1 mole Al2(SO4)3 = 12 moles O atoms = 12 x A.N. O atoms
1 mole Al2(SO4)3 = 3 moles S atoms = 3 x A.N. S atoms
1 mole Al2(SO4)3 = 2 moles Al atoms = 2 x A.N. Al atoms
Conversion Factors in a Molecular Formula
H2O (l)






1 molecule of H2O = 2 H atoms and 1 O atom
Molecular mass = (2 x 1.008) + 15.99 = 18.00 amu
Molar mass = 18.00 g/mol H2O
1 mole of H2O = 6.022 x 1023 molecules of H2O
1 mole of H2O = 2 mol H atoms = 2 (6.022x1023) H atoms
1 mole of H2O = 1 mol O atoms = 1 (6.022x1023) O atoms
19
Conversion Among Different Quantities
20
Practice Problem
1.
2.
3.
4.
21
Silver is often used in jewellery and tableware.
How many grams of Ag are in 0.0342 mol Ag?
Iron, the main component of steel, is the most
important metal in industrial society. How many
Fe atoms are in 95.8 g of Fe?
Urea, (NH2)2CO, is a nitrogen-containing
compound used as a fertilizer. How many
molecules of urea are in a 25.6 g sample?
How many hydrogen atoms are present in a
25.6 g sample of urea, (NH2)2CO?
Practice Problem

The plant photosynthetic pigment
chlorophyll contains 2.68% magnesium by
weight. How many atoms of Mg will there
be in 1.00 g of chlorophyll?
22