Matter and Chemical
Change
Final Exam Review
Key Concepts
• Workplace
Hazardous Materials
Information System
(WHMIS) and safety
• Substances and
properties
• Endothermic and
exothermic reactions
• Reactants and
products
• Conservation of mass
• Factors affecting
reaction rates
• Periodic table
• Elements,
compounds and
atomic theory
• Chemical naming
Safety
• All chemicals should be treated with respect.
• The WHMIS safety symbols have been adopted
to safeguard the classroom, home, and
workplace.
Particle Model of Matter
• All matter is made of extremely tiny particles
(atoms)
• Each pure substance has its own kind of particle,
different from the particles of other pure
substances
• Particles attract each other
• Particles are always moving
• Particles at a higher temperature move faster on
average than particles at a lower temperature
Classification of Matter
Pure Substances
Elements
Mixtures
Compounds
Heterogeneous
Mixtures
Ordinary
Mechanical
Mixtures
Suspensions
Homogeneous
Mixtures
Colloids
Physical and Chemical Changes
• Physical property: an observable characteristic
of matter
• Physical change: change in form but not in
chemical composition; no new substances are
formed
• Chemical property: a characteristic of matter
that describes how it reacts when undergoing a
chemical change
• Chemical change: a change in which one or
more new chemical substances are formed
The Periodic Table
• Elements are organized into a periodic table
according to similarities in their properties.
• Groups: vertical columns; elements in the same
group share similar chemical properties
• Periods: horizontal rows, ordered according to
atomic number
• Many scientists, including Mendeleev, Dalton,
Thomson, Rutherford, and Bohr helped to
develop the modern view of the elements,
compounds, and atoms.
Chemistry Laws
• The Law of Conservation of Mass and the Law of
Definite Composition help explain the behaviour of
elements and compounds in chemical reactions.
• Law of Conservation of Mass: in a chemical change,
the total mass of the new substances is always the
same as the total mass of the original substances
• Law of Definite Composition: compounds are pure
substances that contain two or more elements
combined together in fixed (or definite) proportions
The Building Blocks of Atoms
• Atoms are composed of small particles including
electrons, protons, and neutrons.
• # of electrons = atomic number
• # of protons = atomic number
• # of neutrons = atomic mass – atomic number
(rounded to the nearest whole number)
Element Categories
• Elements can be divided into metals,
non-metals, and metalloids depending on their
physical and chemical properties.
Element Categories
• Metals are located to the left of the staircase on
the periodic table
• Non-metals are located to the right of the
staircase on the periodic table
• Metalloids are located along the staircase on the
periodic table
Chemical Formulas
• Chemical symbols are used to represent
elements and compounds.
Cu(𝑠) , Fe(𝑠) , H2(g) , H2 O(𝑙) , CO2(g) , NaCl(𝑠) , CaO(𝑠)
• Chemical equations are used to represent
chemical reactions.
H2 O(𝑙) + CO2(g) → C6 H12 O6(s) + O2(g)
Evidence of Chemical Reaction
Evidence that a chemical reaction has occurred
includes:
• the creation or absorption of energy (heat, light)
• a precipitate is formed
• a gas is formed
• a change in colour
• a change in odour
Ionic Compounds
• Ionic compounds are composed of metals and
non-metals
• To name an ionic compound:
• The name of the metal goes first
• The name of the non-metal goes second, and the
ending of the non-metal should be changed to
“ide”
• Ex: CaCl2 : calcium chloride
Molecular Compounds
Molecular compounds are composed of only nonmetals
• A molecular compound made up of one or more
atoms of the same element keeps the name of the
element.
• To name a molecular compound composed of two
different kinds of elements:
• Element names go in the same order in which they
appear in the chemical formula
• Prefixes are used to identify how many atoms of each
element are present
• The ending of the second element should be changed
to “ide”
Molecular Naming Prefixes
1.
2.
3.
4.
5.
mono
di
tri
tetra
penta
6. hexa
7. hepta
8. octa
9. nona
10.deca
Reaction Types
• Exothermic reactions produce/release energy
(usually heat)
• Endothermic reactions require/absorb energy
(usually heat)
Reaction Rates
• Catalyst: a substance that speeds up a chemical
reaction without being used up in the reaction
• Inhibitor: a substance that slows down or
prevents a chemical reaction from taking place
• Other factors affecting reaction rates include
temperature, stirring, surface area of reactants,
and size of the mixing container
Corrosion
• Some metals corrode when they are exposed to
air and moisture.
• Air is a reactant in this reaction
• Water is a catalyst in this reaction
• Corrosion: a process whereby metals or stone
are chemically degraded or broken down
Chemistry
• Combustion is a highly exothermic combination
of a substance with oxygen.
• The products of combustion are always carbon
dioxide and water vapour.
What to Expect on the PAT
From this unit:
• 10 multiple choice questions
• 1 numerical response question
• 5 “knowledge” questions
• 6 “skills” questions
Do I Get a Periodic Table?
Examples of Knowledge
Questions
Which of the following
events is an example
of a chemical change?
In most corrosion and
combustion reactions,
__i__ is a __ii__.
A. Liquid nitrogen
evaporates
B. A candle burns
C. Water boils
D. Ice melts
The statement above is
completed by the
information in row
Examples of Skills Questions
What is the chemical name of a
molecular substance that is
composed of one carbon atom
and four chlorine atoms?
A student burns a piece of
magnesium that has a mass of
70.2 g and makes the following
observations.
A.
B.
C.
D.
• Heat is generated.
• An intense white light is
emitted.
• A mass of 130.8 g of
white magnesium oxide
ash is produced.
Carbon tetrachlorine
Carbon tetrachloride
Carbon chlorine
Carbon chloride
The mass of oxygen that
reacts in the chemical
reaction described above is
_______g.