When a lump of zinc is added into copper sulfate solution, the two slowly react to produce very small dark copper granules and zinc sulfate solution.

1. Write down the word equation

2. Write down the symbol equation

3. Define ‘displacement reaction’

1. Write down the chemical formulae for these ionic compounds:

a) Silver Chlorideb) Magnesium Sulfatec) Sodium Hydroxided) Barium Carbonatee) Potassium Nitratef) Iron (II) Sulfateg) Zinc Hydroxide

2. Circle the insoluble compounds

Chemical EquationsEvery chemical reaction has:• reactants (the stuff that react) and;• products (the stuff produced)And the chemical equation always looks like:

Reactant(s) → Product(s)

There are TWO types of chemical equations:

1. Word Equation

Calcium + Water → Hydrogen + Calcium Hydroxide

2. Symbol Equation

Ca + H2O → H2 + Ca(OH)2

One is simply the translated version of the other.

EXAMPLE ONE

Magnesium burns very brightly when heated. After the combustion, magnesium oxide (the white powder/ash) remains.

1. What are the reactants? (hint: when something “burns” it reacts with oxygen)

2. What is the product?

3. Write down the chemical equation.

EXAMPLE ONE

EXAMPLE TWOCalcium metal reacts violently with water, producing hydrogen gas and calcium hydroxide.

1. Reactants:

2. Products:

3. Chemical equation:

EXAMPLE THREEWhen sodium hydroxide and barium nitrate are mixed together, white/cloudy precipitate is formed.

1. Reactants:

2. Products:

3. Word equation:

4. Symbol equation:

When a lump of magnesium is dropped into a pool of hydrochloric acid, they react violently, producing hydrogen gas and magnesium chloride solution.

Word Equation:

Symbol equation:HCl + Mg → H2 + MgCl2

HydrochloricAcid + Magnesium → Hydrogen

Gas + MagnesiumChloride

HCl + Mg → H2 + MgCl2

But there is a small problem…

1. Compare the number of hydrogen atoms on each side

2. Compare the number of chlorine atoms (ions) on each side

This is an ‘unbalanced’ symbol equation

*Balancing Symbol EquationsBalance the equation by writing the number(s) in front of the reactant(s) and/or product(s).

HCl + Mg → H2 + MgCl2

Is this equation now balanced?Note: NEVER EVER change the formula of reactants or products

2

Balanced or Unbalanced?

a) H2 + O2 → H2O2

b) NaCl + AgNO3 → AgCl + NaNO3

c) CuSO4 + Zn → ZnSO4 + Cu

d) NaOH + ZnSO4 → Na2SO4 + Zn(OH)2

e) HCl + NaOH → NaCl + H2O

f) Mg + O2 → MgO

g) H2 + O2 → H2O

h) CaO + HCl → CaCl2 + H2O

Balanced or Unbalanced?

a) H2 + O2 → H2O2

b) NaCl + AgNO3 → AgCl + NaNO3

c) CuSO4 + Zn → ZnSO4 + Cu

d) NaOH + ZnSO4 → Na2SO4 + Zn(OH)2

e) HCl + NaOH → NaCl + H2O

f) Mg + O2 → MgO

g) H2 + O2 → H2O

h) CaO + HCl → CaCl2 + H2O

2

222 2

2

Copy all equations; find the THREE unbalanced equations and balance them.

a) Zn + Pb(NO3)2 → Pb + Zn(NO3)2

b) Mg + O2 → MgO

c) Fe + CuSO4 → Cu + FeSO4

d) H2O → H2 + O2

e) HNO3 + Na2CO3 → NaNO3 + H2O + CO2