Final Review
Measurement
• Accuracy
• Precision
• What are the rules for
reading instruments in
the lab?
• How do you decide
the best instrument to
use in the lab?
Significant Figures
•
•
•
•
•
•
What are the rules?
0.5260
5.02
5020
0.00502
500.
Significant Figures
• What are the rules for addition and
subtraction?
• 5.20 + 6.2 =
5.21 – 5.234 =
• What are the rules for multiplication and
division?
• 5.02 x 5.203 =
5.54 x 5.4/5 =
Chemical and Physical Change
• How do we know something is a chemical
change?
• What are some chemical changes?
• How do we know something is a physical
change?
• What are some physical changes?
Chemical and Physical Properties
• What is a chemical property? Physical
property?
– Melting point
– Corrosive
– Solubility
– Density
– Boiling point
- length
- toxicity
- mass
- Flammability
- combustibility
Atomic Structure
• What is an isotope?
80
35
Br
Carbon- 12
32
16
S
• How many protons,
neutrons, and
electrons?
Atomic Structure
Element
Atomic
Mass
Sodium -24
Oxygen-18
Protons
Neutrons
11
18
Calcium-41 41
11
10
20
Electrons
10
18
Electron Configuration
Electron Configuration
• What is the electron configurations for:
– Sodium
– Fluorine
– Phosphorus
– Calcium
– Iron
– Bromine
What are the shorthand configurations?
Ionization energy, electronegativity
Electron affinity INCREASE
Atomic size increases,
shielding constant
Ionic size increases
Periodic Trends
• Which atom is larger and has the greater
electronegativity?
– Sodium or chlorine
– Magnesium or barium
– Oxygen or lithium
• Which ion is smaller?
– Calcium or barium
– Magnesium or silicon
– Chlorine or silicon
Compounds
• Identify each of the following as ionic or
covalent. Write the name of each
compound.
– NaBr
– P3N7
– O4Br6
– Ca3N2
– B2I8
F3H9
Mg3P2
NaCl
SrI2
BaBr2
Two Types of Compounds
Smallest
piece
Types of
elements
State
Melting
Point
Ionic
Molecular
Formula Unit
Molecule
Metal and
Nonmetal
Nonmetals
solid
Solid, liquid
or gas
High >300ºC
Low <300ºC
Naming Compounds
• Identify each of the following as ionic or
covalent. Write the name of each
compound.
– NaBr
– P3N7
– O4Br6
– Ca3N2
– B2I8
F3H9
Mg3P2
NaCl
SrI2
BaBr2
Write the formulas for these
•
•
•
•
•
•
•
•
Lithium sulfide
tin (II) oxide
tin (IV) oxide
Magnesium fluoride
Copper (II) sulfate
Iron (III) phosphide
gallium nitrate
Iron (III) sulfide
Covalent Bonds
Polar-Covalent bonds
 Electrons are unequally shared
 Electronegativity difference between .3 and 1.7
Nonpolar-Covalent bonds
 Electrons are equally shared
 Electronegativity difference of 0 to 0.3
Polarity
A molecule, such as HF, that has a
center of positive charge and a center
of negative charge is said to be polar,
or to have a dipole moment.
H F
+

Polar/Non-Polar
•
•
•
•
•
•
O2
CH3Cl
HCl
CCl4
N2
NO2
Single Replacement Reactions
 Br2 (l) + NaI (aq) 
 Ca (s) + HBr
(aq)

 Cu(NO3)2 (aq) + Au (s) 
 Fe
(s)
+ H2SO4 (aq) 
Double Replacement
1. NaCl
(aq)
+ AgNO3 (aq) 
2. SrBr2 (aq) + AgNO3 (aq) 
3. Li2SO4 (aq) + Pb(NO3)2 (aq) 
4. K2CO3 (aq) + Pb(NO3)2 (aq) 
Calculating Formula Mass
Calculate the formula mass of magnesium carbonate,
MgCO3.
24.31 g + 12.01 g + 3(16.00 g) = 84.32 g
Calculations with Moles:
How many grams of lithium are in 3.50 moles of
lithium?
3.50 mol Li
6.94 g Li
1 mol Li
=
24.29 g Li
Calculations with Moles:
Converting grams to moles
How many moles of lithium are in 18.2 grams of
lithium?
18.2 g Li
1 mol Li
6.94 g Li
=
2.62
mol Li
Calculations with Moles:
Using Avogadro’s Number
How many atoms of lithium are in 3.50 moles of
lithium?
3.50 mol Li 6.022 x 1023 atoms Li
1 mol Li
= 2.11 x 1024 atoms Li
Calculations with Moles:
How many atoms of lithium are in 18.2 g of
lithium?
18.2 g Li 1 mol Li
6.94 g Li
6.022 x 1023 atoms Li
1 mol Li
(18.2)(6.022 x 1023)/6.94
= 1.58 x 1024 atoms Li
Periodic
Table
Mass
gA
Balanced
Equation
Moles
A
Periodic
Table
Moles
B
Mass
gB
•Decide
where to start based on the units you
are given
•and
stop based on what unit you are asked for
For example...
• If 10.1 g of Fe are added to a solution of
Copper (II) Sulfate, how much solid copper
would form?
• Fe + CuSO4  Fe2(SO4)3 + Cu
• 2Fe + 3CuSO4  Fe2(SO4)3 + 3Cu
10.1 g Fe 1 mol Fe 3 mol Cu 63.55 g Cu
55.85 g Fe 2 mol Fe 1 mol Cu
= 17.3 g Cu
Calculations involving Specific
Heat
cp = ___q__
m x T
OR
q = cp x m x T
cp = Specific Heat
q = Heat lost or gained
T = Temperature change
Gas Laws
1 A gas mixture containing O2, N2, and CO2 has
a pressure of 250 mm Hg. If the pressure of
O2, is 50 mm Hg and the pressure of N2 is 175
mm Hg, find the pressure of CO2.
2 Five liters of air at –50 C is warmed to 100
C. What is the new volume if the pressure
remains constant?
3 How many moles of gas are present if the
volume is 2.5 L, pressure is 0.95 atm, and
temperature is 25 C?
Gas Laws
• How many moles of air are there in a 2.0 L
bottle at 19ºC and 747 mm Hg?
• What is the pressure exerted by 1.8 g of
H2 gas exert in a 4.3 L balloon at 27ºC?
Molarity
• What is molarity?
• What is the molarity of a solution prepared by
dissolving 16.0 g of BaCl2 in enough water to
give 450 ml of solution?
• What is the molarity of the solution produced
when 145 g of sodium chloride is dissolved in
sufficient water to prepare 2.75 L of solution?
• How many grams of potassium chloride are
needed to prepare 0.7500 L of a 1.50 M solution
of potassium chloride?
Titration Practice
1. If it takes 250 mL of 0.5 M LiOH to neutralize 50 mL
of an HNO3 solution, what is the concentration of the
HNO3?
2. If it takes 100 mL of 1.0 M HCl to neutralize 250 mL
of Ca(OH)2 solution, what is the concentration of the
Ca(OH)2 solution?
3. If it takes 50 mL of 0.5 M KOH solution to completely
neutralize 125 mL of sulfuric acid solution (H2SO4),
what is the concentration of the H2SO4 solution?
Rate of Reaction
• What are the factors that increase the rate
of reaction?
Table – VSEPR Structures