National 5
Chemistry
Unit 1
Chemical Changes and Structure
Sub Section 1
Chemical Reactions and Substances
1
1. Making new substances
What happens when one substance is added to another?
Sometimes nothing happens, but at other times a chemical reaction takes
place.
What happens in a chemical reaction?
-
The starting substances react together and are changed into new
substances.
Many chemical reactions are accompanied by a noticeable change in
appearance of a substance including
- colour changes
- gases given off
- solids forming.
- energy change
Activity 1.13
Signs of a Chemical Reaction
Follow the instructions to carry out a number of different activities to find out
if a chemical reaction has occurred or not.
(you may want to make notes in the back of your jotter as you go along)
Copy the following table into your notes
Substances added
together
SAFETY
What is observed?
Chemical reaction
(yes or no)
Take care with acids and alkalis.
1.
Magnesium and copper sulphate solution
(a).
Add copper sulphate solution to a depth of 2 cm.
(b). Add a 1 cm piece of magnesium and shake the mixture.
Leave the reaction mixture to settle for a few minutes.
2
Observe what happens.
2
Repeat the above procedure using:




1.
vitamin C tablet and water,
sand and water,
magnesium ribbon ( 1 cm) and hydrochloric acid,
copper turnings and hydrochloric acid.
Ammonium chloride and calcium hydroxide solids
(a). Add 2 spatulafuls of ammonium chloride onto
a watch glass.
(b) Add 2 spatulafuls of calcium
hydroxide and mix the substances together
with the spatula. Smell the reaction mixture
very cautiously.
4
Repeat this procedure using
copper oxide and salt
5
Sodium carbonate and lead nitrate solutions
(a) Add sodium carbonate solution to a depth of 2 cm.
(b).
Add a few drops of lead nitrate solution and
leave the reaction mixture to settle for a few
minutes.
6.
Repeat this procedure using:



sodium chloride and potassium nitrate solutions,
barium nitrate and sodium sulphate solutions,
copper nitrate and potassium chloride solutions.
3
Answer the following questions
1
What is meant by a chemical reaction?
2. What are the 4 ways of recognising that a chemical reaction is taking
place?
3. Ensure that you have completed the table
Collect Handout 1 and stick it into your notes.
Extension
Collect a Standard Grade textbook and answer questions 1 and 2.
Homework
Exercise 1.1 Chemical Reactions
4
2. Energy changes
When some substances are added together, nothing appears to happen. However, a
chemical reaction may still be taking place. How can we tell?
Often this can be detected using a thermometer. This is because all chemical reactions
involve energy changes and for some reactions this is great enough to be observed.
Exothermic reactions release energy to the surroundings so that the surroundings
(and the reaction mixture) heat up. An explosion is a chemical reaction in which a lot
of energy is given out in a very short time.
Endothermic reactions take in energy from the surroundings so that the
surroundings (and the reaction mixture) lose heat, i.e. cool down.
Activity 1.14
Energy in a Chemical Reaction
Copy and complete the following table.
Solutions added
together
SAFETY
Temperature change
(yes or no)
Chemical reaction
(yes or no)
Take care with acids and alkalis.
Hydrochloric acid and sodium hydroxide solution
.
1. Add 20 cm3 of hydrochloric
acid to a small beaker.
Measure the temperature of
the acid.
2.
Quickly add 20 cm3 of sodium
hydroxide to the acid.
Measure the highest temperature reached by
the reaction mixture
5
3.
Repeat the previous procedure using:

hydrochloric acid and nitric acid,

sodium chloride and potassium nitrate solutions,

sulphuric acid and potassium hydroxide solution.
Your teacher may show you a demo of barium hydroxide and ammonium
thiocyanate.
Answer the following questions
1. If there is no visible sign, what is a way of identifying that a chemical
reaction is taking place?
2. What is meant by an exothermic reaction?
3. What is meant by an endothermic reaction?
6
Extension activity
3. A need for energy
Some chemical reactions do not take place on their own. For example, photosynthesis needs
energy from the sun to make it happen.
Energy is often needed to get the reaction going and sometimes to keep it going.
Different kinds of energy can be used to start different reactions, e.g. heat energy to start the
reaction of magnesium and oxygen, electrical energy to break up copper chloride.
Activity 1.15
Energy needs in a Chemical Reaction
Copy and complete the table below.
Compound heated
What is observed
Chemical reaction
(yes or no)
Your teacher will get you to complete a Practical Assessment on
‘Heating Solids’
Use Handout 2
7
Answer the following question
What is often needed to start a chemical reaction?
Success task / homework
Split your page into quarters.
In each quarter write one of the following headings
At home
In school
Outside
Industry
Write down as many chemical reactions as you can for each group.
Share your answers with your partner.
Combustion
Read and complete
Handout 3
Making Compounds by Combustion
8
4. Word Equations
How can we describe a reaction in a simpler way?
So far we have looked at many different chemical reactions.
Sometimes, as chemists, it is useful to describe chemical reactions in a simpler way.
A word equation is a simpler way to describe a chemical reaction.
There are a number of steps to remember when writing a word equation.
1. Draw an arrow in the middle of a line.
2. Write the names of the chemicals we start with on the left of the arrow and
separate them by + signs.
3. Write the names of the chemicals that are made on the right of the arrow
and separate them by + signs.
Look at the example below.
When a candle burns, it reacts with oxygen and the new substances that are made are
water and carbon dioxide.
The word equation for this reaction will be:
candle + oxygen
water +
carbon
dioxide
Stick NOTES 1.30 into your notes
Write a word equation for each reaction below.
1
If silver (I) oxide is heated it can be turned into silver and oxygen.
2
Petrol burns in oxygen to make carbon dioxide and water.
3
Sugar burns in oxygen to make carbon dioxide and water.
9
4
A pupil burned a fuel called “fast gas” and found that carbon dioxide, water
and sulphur dioxide were made.
(a) Write a word equation for the reaction.
Think about the atoms that are present in the new substances.
Think about the atoms in the reactants.
(b) What does this tell you about the elements that must be present in the “fast
gas”? If you are unsure see your teacher for help.
(c) Explain your answer to question (b)
Complete Exercise 1
10
5. State symbols
As we have seen, word equations describe a chemical reaction, but how do I know if
we are supposed to use solid copper sulphate or copper sulphate solution in a
reaction?
It is usual when writing chemical equations to show the states of all the reactants and
all the products. (i.e., whether they are solids, liquids or gases)
We do this by writing subscripts in the same line as the chemical formula of the
substance.
The subscripts we use are:(s) stands for solid
so copper metal would be
written as Cu(s)
(g) stands for gas
so argon gas would be
written as Ar(g)
(l) stands for liquids (water, alcohol, mercury)
so water is written as
H2O(l)
(aq) stands for aqueous solutions (dissolved in water)
so hydrochloric acid
solution is written as
HCl(aq)
Complete the card sort activity ‘Word Equations’
Homework Exercise 1.14
11
6. Chemical Formula
How do we know that the formula of water is H2O?
We can work out the chemical formula of a substance easily by following the steps on
the FORMULA NOTES sheet.
Collect the FORMULA notes sheet and stick it into your jotter.
It will make writing formula a lot easier if you remember this table which uses
information from the Periodic Table.
GROUP
1
2
3
4
5
6
7
8
VALENCY 1
2
3
4
3
2
1
0
Answer the questions on Exercise 2 using the Steps in the Formula Sheet
to help you.
NB – write down the letters
S
V
S
S
Use the Formula
Sheet to help if you
can’t remember
what each word
means
F
at the side of the page for each formula, as in the example on the sheet.
After you have completed 5 questions check your answers with your partner and
analyse any you have got wrong.
Do Exercises 2 and 3
12
7. Meaningful names
Copy and complete the table below.
Prefix
Meaning
Compound
mono
carbon monoxide
di
tri
tetra
sulphur dioxide
sulphur trioxide
carbon tetrachloride
Formula
Now write down the formula of the following compounds:
1.
2.
3.
4.
5.
6.
nitrogen dioxide
nitrogen monoxide
carbon dioxide
phosphorus trichloride
dinitrogen tetraoxide
Carbon tetrafluoride
8. Transition Metals and Group Ions
Transition Metals
The transition metals do not fit into a group of the periodic Table as in the table used
before.
Collect NOTES 1.26 and stick it into your notes.
Carry out Exercise 4
Group Ions (‘ates’ and ‘ites’)
Sometimes atoms exist as a group of atoms which tend to stay together during
reactions.
Collect NOTES 1.27 and the comples formula sheet and stick them into your jotter.
Carry out Exercise 5
13
To do:
Draw a cartoon strip that would show that you understand how to either
OR
(a) write a word equation
(b) work out the formula of a compound
Extension
Standard Grade textbook Page 76 Questions 15.16 and 17
Homework
Exercise 1.13 (ii)
14
8 Balanced Chemical Equations
Can we make an equation give us even more information ?
Now that we are able to write the formula of a compound we can write a balanced
chemical equation – this gives us much more information than a word equation as it
can be used to tell us how much of each reactant we need in a reaction – and also how
much product we could make.
Your teacher will use some examples to show you how to balance a chemical
equation.
Collect NOTES 1.32 (there are 2 sheets) and stick them into your notes.
Complete Exercise 6
Extension
Standard Grade textbook Page 45 Qu 16
Homework
Exercises 1.14, 1.15, 1.16
Summary Task
What have I learned ?
Design a SUMMARY SHEET to show the steps involved in writing a BALANCED
CHEMICAL EQUATION when you have been given a word equation.
Your summary can be in the form of a
- LEAFLET
- FLOW DIAGRAM
- POSTER
You must include
- how to work out the fomula of a compound
- transition metals
- group ions
- how to balance an equation.
15
Consolidation Exercises
Exercise 1 Word equations
1. Write each of the following chemical reactions in the form of a word
equation.
a) Hydrogen joins up with oxygen to make water.
b) Carbon dioxide and water vapour are produced when methane gas
reacts with oxygen.
c) Iron metal is formed when iron oxide is heated with carbon monoxide.
Carbon dioxide is also formed.
d) In a car engine petrol reacts with oxygen to form carbon dioxide and
water vapour.
e) The reaction of dilute hydrochloric acid with calcium carbonate
produces calcium chloride, carbon dioxide and water vapour.
f)
Silver oxide breaks up when heated to form the elements.
g) Ammonium sulphate is a fertilizer produced by the reaction of
ammonia with dilute sulphuric acid.
2. Write a word equation with state symbols for each of the following
reactions.
a) the reaction of carbon powder with oxygen gas to form carbon dioxide
gas
b) the reaction of zinc metal with copper sulphate solution to form copper
metal and zinc sulphate solution
c) the reaction of magnesium metal with oxygen gas to form the
powdered compound
d) the reaction of sodium metal with water to form sodium hydroxide
solution and hydrogen gas
e) the reaction of barium chloride solution with sodium sulphate solution
to form solid barium sulphate and sodium chloride solution
16
Exercise 2
Using the Periodic Table
Write the formula for each of the following compounds.
a)
b)
c)
d)
e)
f)
g)
h)
Exercise 3
hydrogen chloride
phosphorus hydride
nitrogen fluoride
silicon hydride
silicon oxide
hydrogen sulphide
nitrogen hydride
silicon chloride
Using the Periodic Table
Write the formula for each of the following compounds.
a)
potassium chloride
b)
calcium fluoride
c)
sodium sulphide
d)
calcium oxide
e)
aluminium sulphide
f)
magnesium fluoride
g)
lithium bromide
h)
aluminium chloride
i)
magnesium nitride
17
Exercise 4
Using Roman numerals
Write the formula for each of the following compounds.
a)
b)
c)
d)
e)
f)
g)
iron(III) chloride
copper(II) oxide
copper(I) chloride
iron(II) bromide
lead(I) oxide
vanadium(V) oxide
copper(II) bromide
h)
lead(IV) oxide
Exercise 5
Using group ions
Write the formula for each of the following ionic compounds.
a)
b)
c)
d)
e)
f)
g)
h)
i)
j)
k)
l)
m)
n)
o)
p)
sodium sulphate
potassium nitrate
calcium carbonate
magnesium hydroxide
ammonium chloride
lithium sulphate
aluminium carbonate
lithium carbonate
ammonium hydroxide
aluminium hydroxide
ammonium sulphate
sodium phosphate
potassium hydroxide
radium sulphate
sodium sulphite
ammonium carbonate
18
Exercise 6
1.
Balanced chemical equations
Balance each of the following chemical equations.
a)
H2
+
Cl2
→
HCl
b)
N2
+
O2
→
NO2
c)
Al
+
Cl2
→
AlCl3
d)
C3H8
+
O2
→
CO2
e)
H2
+
O2
→
H2O
f)
Ca
+
H2O
→
Ca(OH)2
g)
Fe2O3
+
CO
→
h)
NH3
+
O2
i)
C2H6
+
j)
NaOH
+
+
H2O
Fe
+
CO2
→
NO
+
H2O
O2
→
CO2
+
H2O
H2SO4
→
Na2SO4
+
H2O
2. Write word equations for each of the following reactions and hence write
balanced chemical equations.
a)
the burning of carbon to give carbon dioxide
b)
the burning of calcium
c)
the formation of magnesium nitride from its elements
d)
the formation of titanium(IV) chloride from its elements
e)
the decomposition of hydrogen bromide
f)
the formation of sulphur trioxide from sulphur dioxide and oxygen
g)
the burning of silicon
h)
the decomposition of nitrogen hydride to produce the elements
i)
the decomposition of silver(I) oxide
19
Exercise 7 Using symbols and formulae
Use symbols and formulae to write a balanced chemical equation, with the state
symbols, for each of the following reactions.
a)
carbon monoxide gas + oxygen gas
b)
sodium metal + water
c)
lead(II) +
nitrate
e)
aluminium metal
f)
iron metal
g)
magnesium +
h)
nitrogen gas
+
+
→
lead(II) chloride solid + potassium
nitrate solution
calcium oxide powder
→
oxygen gas
chlorine gas
→
i)
ammonia
+
(nitrogen hydride) gas
hydrogen gas
sulphuric acid,
H2SO4(aq)
barium +
sodium
chloride
sulphate
→
+
carbon dioxide
gas
aluminium oxide solid
iron(III) chloride solid
→
nitric acid, HNO3(aq)
+
carbon dioxide gas
sodium hydroxide solution + hydrogen gas
potassium
→
chloride solution
d) calcium carbonate powder
j)
→
→
→
→
magnesium + hydrogen
nitrate solution
gas
ammonia gas
ammonium
sulphate solution
barium
+
water
+ sodium chloride
sulphate
20
National 5
Elements,
Compounds and
Mixtures
21
1. Elements
1.1. Organising Elements – The Periodic Table
Are all the elements in the known world the same?
Students in school are gathered together by age and subject being
studied to form a class. In a supermarket, similar foods are
gathered together, e.g. fruit, cereals, meat.
When we are faced with a wide variety of things we often try to
gather together those which have something in common.
This is called classification.
Elements are the building blocks of all substances in the world
just as bricks are the building blocks of houses. Just over 100
different elements are known.
There are different ways of gathering the elements together so that
all the elements in the one "class" have something in common.
Modern-day chemists have classified elements by arranging them
in the Periodic Table.
Activity 1.1
Using
the
information
above
answer
question 1 & 2 over the page. Now look at
samples of some of the elements also look
at a suitable Periodic Table. Complete the
3 tables over the page as you go through
the 6 stages of the activities.
22
1. Find some
-
shiny elements,
coloured elements.
2. Find some
-
metal elements,
non-metal elements.
3. Find some elements which are -
solid
at
room
temperature,
-
liquid
at
room
-
gas at room temperature.
4. Find some elements which are
-
naturally occurring,
made by scientists.
5. Find some elements which are
-
stored under oil.
6. Find some elements which are
-
named after a planet,
named after a scientist,
named after a place.
temperature,
23
Questions:
1. Approximately how many different elements are known?
2. What name is given to the modern-day arrangement of elements?
3.
Copy and complete the following tables.
Include a number of elements under each heading.
Solid
Liquid
Gas
Metal
Non-metal
Naturally occurring
Made by scientists
1.2 Chemical symbols
Why does sodium not have the symbol S?
A chemical symbol is a "shorthand" way of representing an element.
Each element has its own chemical symbol.
The ancient chemists (or alchemists) were the first to use symbols for elements in
place of their names,
e.g.
Modern symbols for elements consist of one or two letters. The first letter is
always a capital letter; the second is always a small letter.
A few elements have symbols which come from the Latin name. For examples the
Latin name for sodium is natrium and for silver it is argentum.
24
Activity 1.2 Elements and Symbols
Look at a suitable Periodic Table and use text book page…. to find some
elements which have a symbol

that is the first letter of its name,

that is the first two letters of its name,

that comes from its Latin name.
1.
Copy and complete the following table remembering that a capital
letter is used for the symbol.
Element
Symbol
hydrogen
C
iodine
N
sulphur
V
2.
Copy and complete the table below remembering that only the first
letter of the symbol is a capital letter.
Element
Symbol
chlorine
Mg
calcium
Sc
argon
Si
3.
What is the symbol for helium?
4.
Why is it not just H?
5.
What is the symbol for cadmium?
6.
Why is it not just C or Ca?
25
7.
Copy and complete the following table.
Element
Symbol
Latin name
gold
silver
iron
sodium
potassium
Extension: Make up your own element with its own unique properties and
symbol. Describe it to your teacher when you have finished.
Families of elements – Groups in the Periodic Table
1.3
Some elements are very reactive; others are quite unreactive. Elements are arranged
into ‘families’ with similar properties called groups.
Activity 1.3 – Reactivity of Group 1 Metals
Your teacher will carry out a demonstration
to show the reactivity of group 1 metals in
water. They will also show you a short DVD(1)
about Group 7 and 8 elements.
Take a copy of Notes 1.1 and stick it into your notes after completing it.
1.
How are the alkali metals stored?
2.
Why are they stored in this way?
3.
Describe the reactions of the alkali metals with water.
4.
Describe a reaction involving chlorine.
5.
Why are the noble gases often referred to as the inert gases?
26
2. Compounds and mixtures
Are you made up of compounds or a mixture of
elements?
2.1
Compounds
Most of the substances which exist in the world are not pure elements - they are
compounds.
A compound is made up of two or more elements which are chemically joined
together. Since they are joined together it is difficult to separate out the elements
which make up the compound. Energy must be supplied to do this.
Some elements, e.g. carbon and oxygen, are found in lots of compounds; other
elements make very few compounds.
Activity 1.4
Look at the display of substances.
Identify the substances which are
1.
- pure elements
- compounds.
What is meant by a compound?
2.
Is it easy to separate out the elements which make
up a compound? Explain.
3.
Copy and complete the following table for the
substances in the display.
Element
Compound
27
2.2
Making and breaking compounds
a) Making magnesium oxide
A compound is very different from the elements which make it up, e.g.
sugar (a white solid) is made from carbon (a black solid) and hydrogen
and oxygen (both colourless gases).
Magnesium oxide can be made by burning magnesium in oxygen.
Activity 1.5
Safety:
DON'T LOOK DIRECTLY AT BURNING MAGNESIUM.
THE BRIGHT LIGHT COULD DAMAGE YOUR EYES.
1.
Using tongs, hold a piece of
magnesium
ribbon (3 cm) in a Bunsen flame until
it
1. Copy and complete
the following table.
burns.
Name
and
Elements
2. Remove the product from the flame
Appearance
examine it.
reacting
Compound
28
(b) Breaking up copper chloride
Electricity can be used to break up copper chloride into its
elements. This process is called electrolysis.
Activity 1.6
1.
Half-fill a small beaker with water.
2.
Add a few spatulafuls of copper chloride.
Stir until it all dissolves.
3.
Gently clean the carbon electrodes
with sandpaper.
4.
Set up the apparatus shown.
5.
Identify the products at the positive
and negative electrodes.
1. What form of energy is used to break up the compound?
2. What is the process called of breaking up a compound using
electricity called?
29
3. Copy and complete the following table.
Name
Appearance
Elements
formed
Compoun
d
2.3
Naming of compounds
Important Rules for Naming Compounds:
 Compounds containing only two elements have
names ending in -ide, e.g. sodium chloride
contains only sodium and chlorine.
 Compounds containing more than two elements,
one of which is always oxygen, have names
ending in -ate or -ite, e.g. copper sulphate
contains copper, sulphur and oxygen.
Activity 1.7
1.
Compounds containing only two elements have what name ending?
2.
Compounds containing two or more elements, one of which is oxygen,
usually
have one of what two name endings.
3.
Name the elements which can be found in the following compounds:
Answer questions 1 & 2 below.
Then look at compounds in the display. Using the rules above
identify the elements in each of the compounds and fill out
the table in question 3.

Lithium fluoride

Magnesium nitride
30
4.

Potassium sulphate

Calcium chloride

Magnesium carbonate

Lithium sulphite

Potassium oxide

Sodium chlorate

Aluminium phosphate
Copy and complete the following table for the compounds in the display.
Compound
2.4
Element present
Mixtures
Did you know that air is a mixture of gases! But what gases are in air?
Very few substances in nature are found on their own - they are
usually mixed with other substances.
A mixture contains two or more substances which have come
together without reacting; the properties of a mixture are the
same as those of the substances in it.
Different elements are chemically joined together in a compound;
the properties of a compound are different from those of the
elements which make it up.
31
Activity 1.8
Look at the samples of pure sulphur, pure iron.
Now you can help your teacher to demo the difference
between a mixture of iron and sulphur and a compound of
iron and sulphur. A magnet can be used to demonstrate
this.
1.
2.
What is the main difference between a mixture and a
compound?
Draw diagrams to show this difference.
3. Describe how to separate a mixture of iron and
sulphur.
Explain.
4.
Can iron be separated from a compound of iron and
sulphur using a magnet?
Explain.
5.
What is the name of the compound made by sulphur
and iron?
6.
Activity: Filtration: Separating a solid from a Liquid
Can you think where you would use filters in your home?
This is an assessable technique.
Filtration apparatus:
32
Insoluble solid (residue) is trapped in the paper
Filter Paper
Filter Funnel
Instructions:
1.
2.
3.
Collect two clean beakers, filter paper, a filter funnel and a retort
stand.
Set up the apparatus as set out above.
Take the filter paper and fold it in half, then half again. Open it
up (it should be a cone shape). Wet the paper slightly and place it
in the filter funnel.
4.
With the second beaker collect some dirty water from the trolley.
5.
Filter the dirty water.
6.
Collect a Practical Technique write up sheet and complete it.
2.4 More Mixtures - Air
The air around us is an example of a mixture of gases.
Dry air contains approximately 78% nitrogen, 21% oxygen and
small
amounts of carbon dioxide, helium, neon, argon and xenon.
Oxygen gas is produced when potassium permanganate is heated.
This can be used to find the test for oxygen.
33
Activity 1.9 – Testing for Oxygen
SAFETY
In this experiment you MUST check with
your teacher before starting.
1.
Clamp at the mouth.
Test-tube is horizontal.
2. Add 2 spatulafuls of potassium
permanganate followed by a
loose plug of rocksil wool.
3. Gentle heat until potassium permanganate begins
to 'crackle'. Check what happens to a glowingsplint held in the test-tube.
1.
Draw a table showing the mixture of gases in air and the percentage (%) they
make up.
2.
Describe the test for oxygen.
3.
Why does the oxygen in the air not give a positive result to this test?
2.5
More Mixtures - Solutions
(a) Solute, solvent and solution
34
A solution is a mixture of a solute which is dissolved in a solvent. Sea water is an
example of a solution. The salt is the solute and the solvent is the water. Together they
make a sea water solution which is a mixture. You cannot see the salt in sea water, but
it can be tasted.
Activity 1.10
1. Add about 20 cm3 of water (the
solvent)
to an evaporating basin
2. Add three spatulafuls of salt (the
solute)
Stir until it all dissolves.
When a solute dissolves in a solvent to form a solution, no new
substance is formed. Solutions are therefore mixtures.
3. Gently heat the solution on a
to solution, the solvent is water. Substances which are
In antripod
aqueous
evaporate
water
and recover
insoluble
in waterthe
may
be soluble
in other solvents, e.g. turpentine
the salt.solvent for paint, acetone dissolves nail polish.
is a suitable
1. Is it easy to separate a solute and solvent from a solution?
2. Write a brief not on how this is done.
3. Using a Chemistry Text book find out the full definitions of solute,
solvent and solution and write them into your notes.
35
(b) Dilute, concentrated and saturated
How do you turn a concentrated solution of orange juice into a
dilute solution of orange juice?
Activity 1.11 – Making a Dilute, Concentrated and
Saturated Solution
1.
Add about 10 cm3 of water to each of five test-tubes.
2.
To the first test-tube add 1 spatulaful of copper sulphate to
make
a dilute solution.
3.
To the second test-tube add 2 spatulafuls of copper sulphate
and so on to make
successively more concentrated solutions.
Carefully shake each test-tube to dissolve as much copper
sulphate as possible.
4.
Observe the colours of the solutions.
Note which test-tubes contain undissolved copper sulphate
(saturated solution)
5.
Dilute the solutions by adding a further 10 cm 3 of water to
each of
the five test-tubes. Again carefully shake each test-tube to
dissolve as much copper
sulphate as possible.
6. Observe what happens to the colours of the solutions.
Note which test-tubes now contain saturated solutions.
Take a copy of Notes 1.2 and stick it into your notes
after completing it.
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Consolidation Activity: Elements, Compounds and
Mixtutres.
1. Collect a Standard Grade Text book and read pages 3 to 7
answering questions 1, 2 and 3 along the way.
2. Turn to page 8 in the text book and answer questions 3 to
10.
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