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Grade 10 Chemistry Review
This package should serve to help jog your memory of grade 10 science. Parts of this package will be explanation; other parts
will be engaging you. Your teacher will work through this package with you.
Section A (recall)
✓ Matter – Substances vs. Mixtures
✓ Physical vs. Chemical Properties
✓ Atomic Structure
✓ Evidence of Chemical Reactions
o There is an unexpected change in
colour
o A gas is produced
o Energy is released or absorbed
o A precipitate forms
Section B
✓ Counting Atoms
✓ Law of Conservation of Mass
Section C
✓ Naming Ionic & Molecular Compounds
and Writing Chemical Formulas
Section D
✓ Balancing chemical reactions
✓ Identifying Reactions
Section E: Writing Balanced Chemical Reactions
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Section B
Counting Atoms
The subscripts will tell you how many atoms of each element there are.
If there are brackets – multiply the subscript outside of the brackets with the subscript inside
If there is a coefficient – multiply the coefficient with the subscript of the element (and the subscript
outside the brackets if brackets exist)
Example:
Type of Atom
2Mg(OH)2
# of Atoms
Total
Now practice on the Counting Atoms Worksheet
Law of Conservation of Mass: The law of conservation of mass states that during a chemical reaction,
the total mass of reactants equals the total mass of products.
LS = RS
# of elements = # of elements
 PRACTICE ON HANDOUT P 27
Section C: Naming Ionic & Molecular Compounds and Writing Chemical Formulas
IONIC COMPOUNDS: Given Formula, Write the Name
Points to remember about naming ionic compounds
1. Write the cation (positively charged atom, usually a metal) first, then the anion (negatively charged
atom, usually nonmetal)
2. Use the name of cation (metal) with a fixed oxidation state (common charge) directly from the periodic
table.
3. The name of the anion will be made from the root of the element's name plus the suffix "-ide."
Write the correct name for:
1. MgS
2. MgF2
3. Sr3P2
4. K2S
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 PRACTICE ON HANDOUT P 45
Let’s go backwards: Given name, write chemical formula
1.
2.
3.
4.
The metal comes first, then the nonmetal.
Use your periodic table to find out the charges of each metal and nonmetal.
The sum of the positive charge and the sum of the negative charges MUST add up to zero.
Use the “criss-cross” method.
a. write out both element’s symbols with their charges
b. “criss-cross” the numbers ONLY
c. reduce to lowest ratio, if needed
Example
Write the formula for cesium oxide. (Here you will need to use the lowest ratio)
1. Write Cs+ and O2¯ right next to each other.
2. The least common multiple between the two charges is 2.
3. This means that +2 is the total positive charge and -2 is the total negative charge needed.
4. Two Cs and one O each provide the needed amount of charge, so the correct formula is Cs2O. (i.e. adjust
the subscripts to get a total charge of zero)
1. aluminum nitride
2. beryllium bromide
3. barium iodide
4. boron phosphide
Binary Compounds of Metals with Variable Charges: Given Formula, Write the Name
The metals involved have AT LEAST TWO possible charges. The nonmetals involved have only one charge.
In most cases, simply “uncrossing” the subscripts will work. But in the case of metals whose charges can be
BOTH 2+ and 4+, a more rigorous method is needed.
Write the name for: PbO2
Steps
1. The first part of the name is the unchanged name
of the first element in the formula.
2a. Multiply the charge of the nonmetal by its
subscript. Ignore the fact that it is negative.
2b. Divide this result by the subscript of the metal.
This is the value of the Roman numeral to use
3. The value of the Roman number equals the positive
charge on the metal in this formula. Write the full
name using the Roman number.
Solution
O2Charge 2, subscript 2
subscript on Pb is 1
2×2=4
4÷1=4
Lead(IV)oxide
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Write the correct name for:
1. CuS: _____________
2. SnO2 : _____________
3. Hg2O : _____________
4. Mn2O3: _____________
Given Name, Write the Formula
1. iron(II) chloride: _____________
2. cobalt(III) phosphide: _____________
3. chromium(II) nitride: _____________
4. lead(IV) nitride: _____________
 PRACTICE IONIC COMPOUNDS: NAMES & FORMULAS WORKSHEET USING TRANSITION
METALS & HANDOUT P44
MOLECULAR COMPOUNDS: Given Formula, Write the Name
Greek prefixes are used:
one
two
three
four
five
monoditritetrapenta-
six
seven
eight
nine
ten
Example #1 - write the name for N2O.
Steps
1. Write the name of the first element. If subscript is 2
or more, add a prefix to the name. DO NOT use a
prefix if the subscript is 1.
2. Write the second element in the same way as ionic
compounds → “ide”. Also add a prefix.
hexaheptaoctanonadeca-
Solution
dinitrogen monoxide
Example #2 - write the name for NO2. ___________________
1. sulfur tetrachloride: ______________
3. chlorine monoxide: _____________

Given Name, Write the Formula
2. diphosphorus pentoxide __________________
4. xenon hexafluoride: _____________
PRACTICE MOLECULAR COMPOUNDS: P46
Compounds Involving a Polyatomic Ion
Given Formula, Write the Name
These ARE NOT binary compounds. They contain three or more elements, as opposed to only two in a binary
compound.
If you see a formula like BaSO4, the name is not barium monosulfur tetraoxide.
Learn to recognize the presence of a polyatomic ion in a formula and know its charge. The cations used will be
a mix of fixed charges AND variable charges. You must know which are which.
Use of Brackets
When more than one polyatomic ion is required, put it in brackets and leave subscript outside.
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Example Fe(NO3)2 → two NO3¯
Without the parenthesis, the formula would be FeNO32
When you say a formula involving parenthesis out loud, you use the word "taken" as in the formula for
ammonium sulfide, which is (NH4)2S. Out loud, you say "N H four taken twice S." OR with the formula for
copper(II) chlorate, which is Cu(ClO3)2. You say " Cu Cl O three taken twice."
Example 1 -Write the name for Fe(NO3)2
Steps
1a. Decide if the cation is one showing variable
charge. If so, a Roman numeral will be needed.
1b. Compute the total charge contributed by the
polyatomic ion
Solution
Fe shows variable charge
NO3¯ has a minus one charge and there are two of
them, making a total of minus 2.
Fe must be a positive two, in order to keep the total
charge of the formula at zero.
nitrate
iron(II) nitrate or ferrous nitrate
2. Determine name of polyatomic ion
Write the name of the following polyatomic compounds:
1. AlPO4 : _____________
2. Mg(OH)2 : _____________
3. Cu(ClO3)2 : _____________
4. manganese(II) sulfate: _____________
1. lithium carbonate : _____________
Given Name, Write the Formula
2. tin(II) hydroxide: _____________
3. silver phosphate: _____________
4. cobalt(III) nitrate: _____________
Acids: Given Formula, Write Name
Acid formulas can be recognized by the element hydrogen present at the beginning of the formula. i.e. HCl(aq),
H2S(aq), HNO3(aq), H2SO4(aq)
1) If the acid has only ONE element besides hydrogen, it is called a binary acid and the name will follow the
pattern:
hydro(element root)ic acid e.g. HCl(aq) is hydrochloric acid
2) If the acid has a polyatomic ion in its formula, it is called an oxyacid and the name will follow the pattern:
(element root)ic acid e.g. HNO3(aq) is nitric acid
Write the name of the following acids:
1) HCl(aq)
1) hydrochloric acid
8) HNO3(aq)
8) nitric acid
2) HClO3(aq)
2) chloric acid
9) H2Se(aq)
9) hydroselenic acid
3) H2S(aq)
3) hydrosulfuric acid
10) HBrO3(aq)
10) bromic acid
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4) HBr(aq)
4) hydrobromic acid
11) H3PO4(aq)
11) phosphoric acid
5) H2CO3(aq)
5) carbonic acid
12) HI(aq)
12) hydroiodic acid
6) HF(aq)
6) hydrofluoric acid
13) H2SO4(aq)
13) sulfuric acid
7) HIO3(aq)
7) iodic acid
Given Name, Write the Formula
1) If the acid starts with the prefix hydro- then the acid formula can be obtained by combining H+ with the
corresponding single-atom anion following the same method as ionic formulas. Acid formulas should always
indicate that they are dissolved in water by using the state symbol (aq).
e.g.
hydrosulphuric acid
H+
S2-
H2S(aq)
2) If the acid does not contain the prefix hydro, the formula can be obtained by combining H+ with the
corresponding polyatomic anion following the same method as ionic formulas. Acid formulas should always
indicate that they are dissolved in water by using the state symbol (aq).
e.g. phosphoric acid H+
PO43-
Write the formulas for the following acids
1) hydrochloric acid
1)
H3PO4 (aq)
8) sulphuric acid
8)
2) carbonic acid
2)
9) hydroiodic acid
9)
3) iodic acid
3)
10) phosphoric acid
10)
4) hydrobromic acid
4)
11) bromic acid
11)
5) chloric acid
5)
12) hydroselenic acid
12)
6) hydrofluoric acid
6)
13) nitric acid
13)
7) hydrosuphuric acid
7)
Bases
Bases are very easy to recognize - they usually contain the hydroxide anion. There are, of course, always
exceptions to this rule. there are two bases that do not have hydroxide anion in
their formula. They are NH3 (ammonia) and any metal carbonates (e.g. Na2CO3, K2CO3, MgCO3)
Examples
sodium hydroxide: NaOH
sodium carbonate: Na2CO3
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Section D: Balancing chemical reactions
Guidelines for Balancing Equations:
1. Write the skeleton equation, and make sure that you have written the formula for each molecule correctly.
2. Balance the atoms that occur in the largest number on either side of the equation first. Leave H, O and other
elements until the end.
3. Balance polyatomic ions of both sides of the equation as a unit.
4. Balance other uncombined atoms and elements such as Na and Br2
5. Balance H and O atoms.
6. CHECK YOUR ANSWER. Remember that your coefficients should be in lowest terms.
Balance the following equations:
SF4 (g)+
H2O(l) →
C3H8(g) +
O2(g)
SO2(g) +
→
CO2(g) +

Al(s) + H2SO4(aq) → Al2(SO4)3(aq) + H2(g)
HF (aq)
H2O(g)
PRACTICE ON HANDOUT P487
Section D: Identifying Reactions
Type of Reaction
Pattern
synthesis
decomposition
single displacement
double displacement
complete hydrocarbon combustion
combustion of an element
neutralization
A + B → AB
AB → A + B
A + BC → AC + B (A = metal)
A + BC → BA + C (A = nonmetal)
AB + CD → AD + CB
CxHy + O2 → CO2 + H2O + energy
A + O2 → AO + energy
acid + base → salt + water
(not all follow this → carbonates as
bases)
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Example
Al2(SO4)3 + 3Ca(OH)2 → 2Al(OH)3 + 3CaSO4
2H2O2 → 2H2O + O2

PRACTICE ON HANDOUT P488
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Section E: Writing Balanced Chemical Reactions
Example sodium nitrate + barium sulphate →
Steps
Solution
1. Use the Type of Reactions chart
Sodium nitrate + barium sulphate → sodium sulphate + barium
above to predict the products
nitrate
2. Write the elements with their
Na+ NO3- + Ba2+ SO42- → Na+ SO42- + Ba2+ NO3charges for each compound
3. Use the rules above for writing
Na NO3 + BaSO4 → Na2SO4 + Ba(NO3)2
formulas given names
4. Balance the equation
2Na NO3 + BaSO4 → Na2SO4 + Ba(NO3)2
Example barium + nitrogen →
Example sodium hydroxide + hydrochloric acid →
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Practice: Identify the type of reaction, predict the product based on the reaction pattern, write the word
equation and balanced chemical reaction.
1. ___Ag + ___Cl2 →
2. ___K + ___H2O →
3.___Fe +___H2SO4→
4. ___CuSO4 + ___BaCl2 →
5. ___Zn + ___H3PO4 → __
6. ___Al(NO3)3 + ___NaOH →
7. ___C25H52 +___O2 →
8. ___Cu + ___AgNO3 →
9. ___Cu +___H2O →
10. ___Cu +___Cl2→
11. ___Mg +___N2→
12. ___C +___O2 →
13.___NaOH + ___H2SO4 →
14. ___Al +___H2SO4→
15. ___C2H6 +___O2→
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