Science 1206 - Unit2 : Chemistry
Test Review:
Topic 1: WHMIS / MSDS


WHMIS: Workplace Hazardous Materials Information System. There are 8 WHMIS symbols, you
are required to recognize the 8 symbols and the hazards that they identify.
MSDS: Material Safety Data Sheet. Define what a MSDS is, why it is important, and know the 9
required sections on an MSDS.
Topic 2: Evidence of physical change.

Be able to give examples of evidence that chemical change has occurred. (Reference your
foldable)
Examples: A new colour appears, Heat or light given off, gas bubbles form, precipitate forms,
process is difficult to reverse.
Topic 3: The periodic table.

Know the 4 main sections of the periodic table (metals, non-metals, metalloids, noble gases). If
given an element, be able to classify it into one of the 4 sections.
Topic 4: Naming Ionic Compounds

Given the name of a compound, determine the formula. (Using the criss-cross method may be
useful)
Examples:
Barium Fluoride
Ba2+
F-

BaF2
Iron(III) Oxide
Fe3+
O2-

Fe(III)2O3
Calcium Sulfide
Ca2+
S2-


Ca2S2
(can be written in a lower ratio)
 CaS
Given the formula of a compound, determine the name.
Examples:
Zn3P2

Zinc Phosphide
Cu(II)O

Copper(II) Oxide
AuBr

Gold Bromide
CsCl

Cesium Chloride

Given the name of an ionic compound with a polyatomic ion, determine the formula.
Examples:
Magnesium Hydroxide

Mg2+
OH-

Mg(OH)2
Ammonium Chloride

NH4+
Cl-

NH4Cl
Chromium(III) Dichromate

Cr3+
Cr2O72- 

Cr2(Cr2O7)3
Given the formula of a polyatomic ionic compound, determine the name
Examples:
AgIO3

Silver Iodate
NH4CN

Ammonium Cyanide
Os(HPO4)2

Osmium Hydrogen Phospate
Sr(C6H5COO)2

Strontium Benzoate
Topic 5: Naming Molecular Compounds

Given the name of the molecular compound, determine the molecular formula
Examples:
Dinitrogen Tetrahydride

N2H4
Carbon Dioxide

CO2
Dichlorine Monoxide

Cl2O
Nitrogen Tribromide

NBr3

Given the formula of the molecular compound, determine the name.
Examples:
S2H2

Disulfur Dihydride
SiO2

Silicon Dioxide
SiC

Silicon Monocarbide
C6H8

Hexacarbon Octahydride
1 = mono , 2 = di , 3 = tri , 4 = tetra , 5 = penta , 6 = hexa , 7 = hepta , 8 = octa , 9 = nona , 10 = deca
Topic 6 : Hydrated Ionic Compounds

Hydrated compounds contain water. Given the name of the compound determine the formula,
or if given the formula determine the name.
Examples:
CuSO4∙5H2O

Copper Sulfate Pentahydrate
Cobalt(II) Chloride Dihydrate
 Co(II)Cl2 ∙2H2O
Topic 7 : Energy levels and valence shells






Electrons are distributed in fixed patterns around the nucleus. The nucleus contains protons (+)
and neutrons (neutral).
The number of protons in an atom cannot change, and can be determined by the atomic
number (i.e. Nitrogen has an atomic number of 7, so it has 7 protons).
A neutral atom has equal numbers of protons and electrons. (total charge = #protons #electrons)
Electrons fill in energy levels by occupying the lowest energy levels first, then the higher energy
levels. ( 2e- in the first shell, 8e- in the next, 8e- in the third, 18e- in the fourth…)
The outer energy level is known as the valence shell. Atoms are stable when the outer shell is
filled. This is why atoms tend to lose or gain electrons to become ions.
Other atoms will share electrons to fill their outer shell. This is known as covalent bonding.
Example: Sulfur
 Valence Shell : 6 eThis is the energy diagram for sulfur. We know it is sulfur
because it has 16 protons, and 16 is the atomic number for
sulfur. A neutral sulfur atom will have 16 electrons as well. (2 ein the first shell, 8 e- in the second shell and the rest will be in
the valence shell , 6e-)
 Valence Shell : 8eSulfur will try to fill its outer shell to become more stable. It can
do that by gaining 2 extra electrons. It will then have 18e- and
16 protons. The charge will be 16 -18 = -2.
Topic 8 : Properties of Ionic and Molecular Compounds
Know the general properties of ionic and molecular compounds:
Ionic Compounds - Solids at room temperature, May or may not be soluble in water, may form
a coloured solution in water if soluble or as a liquid, conduct electricity if soluble, melting points
usually above 300OC.
Molecular Compounds – May be solids, liquids or gases at room temperature, may or may not
be soluble in water, generally form colourless solutions in water, do not conduct electricity if
soluble, melting points usually below 300OC
Topic 9: Molecular and Empirical Formulas, molecule, molecular element




An empirical formula is the lowest ratio of one atom to another in a compound.
A molecular formula is the exact number of each atom in a compound
A molecule is when two or more atoms bond together
A molecular element is when two or more of the same element bond together
o 7 elements exist as Dimolecular elements in nature
o Hydrogen, Nitrogen, Oxygen, Fluorine, Chlorine, Bromine, Iodine
Examples:
Given the molecular formula, determine the empirical formula:
C2H6
 CH3
P4Cl10
 P2Cl5
NOTE: If you are given the empirical formula, you CANNOT determine the molecular formula.
Topic 10 : Acids and Bases
Acids: Acids are Molecules that ionize in water to produce H+ ions, which give acids their
properties.
Properties of Acids:






Conduct Electricity
Turn blue litmus paper red
Taste Sour
React with many metals to produce hydrogen gas, H2(g)
Have a pH value less than 7
Neutralize or partially neutralize bases
Naming acids: General Rules
Name the hydrogen compound like an ionic compound. This is the compound name before it is placed
in water. Then determine the name of the acid when the compound is placed in water.
1.
Hydrogen ______ ide becomes hydro_____ ic acid
eg. HCl  Hydrogen Chloride  Hydrochloric Acid
2.
Hydrogen
ite becomes
ous acid
Eg. HClO  Hydrogen Chlorite  Chlorous Acid
3. Hydrogen
___ate becomes ________ic acid
Eg. H2SO4  Hydrogen Nitrate  Nitric Acid
Carboxylic Acids: Carboxylic Acids are compounds that end in COOH. The Hydrogen in COOH is
the acidic hydrogen, and These acids are commonly referred to as organic acids.
Example: CH3COOH – Acetic Acid (Vinegar)
Bases: Ionic compounds that contain the hydroxide ion OH-, an ion that gives a base it’s
properties.
Properties of Bases:






Conduct electricity
Turn Red Litmus Paper Blue
Taste Bitter
Feel Slippery
Have a pH value greater than 7
Neutralize or partially neutralize acids
Naming Bases: Bases are named exactly as the ionic compound is named
Eg. NaOH  Sodium Hydroxide
Eg. Ca(OH)2  Calcium Hydroxide
Writing the formula for a base:
Follow the rules for ionic compounds
Eg. Barium Hydroxide  Ba2+
OH-  Criss Cross Method  Ba(OH)2
Terms to Know:
Chemistry , Matter , Ionic Compound , Molecular Compound , Valence Shell , Proton , Neutron ,
Electron , WHMIS , MSDS , soluble, insoluble, electrical conductivity, melting point, chemical
property, physical property, solid , liquid , gas.