UNIT06.indd
Statement
Topic
1a
Using scientific ideas and models to explain phenomena and developing them to generate and test theories.
7Ec, 7Ed, 7Ee
1b
Critically analysing and evaluating evidence from observations and experiments.
all
2a
Exploring how the creative application of scientific ideas can bring about technological developments and consequent changes in
the way people think and behave.
7Ed, 7Ee
2b
Examining the ethical and moral implications of using and applying science.
7Ee
3a
Recognising that modern science has its
roots in many different societies and cultures
and draws on a variety of valid approaches
to scientific practice.
7Ea, 7Ec, 7Ed
4a
Sharing developments and common understanding across disciplines and boundaries.
7Ee
Links with other units
7H
Rocks and weathering.
9E
Reactions of metals and metal compounds.
8H
The rock cycle.
Cross-curricular links
Topic
Links
7Eb
Food technology
7Ec,
7Ed
Art
7Ee
Geography
Statement
Topic
2c
Elements and compounds show characteristic chemical properties and patterns in their behaviour.
all
4c
Human activity and natural processes can lead to changes in the environment.
7Eb, 7Ee
Code
Framework threads
Year 7
Topic
1.2a
Using investigative approaches: planning an approach
Describe an appropriate approach to answer a scientific question using a limited range of information and making relevant observations or measurements.
7Ed, 7Ee
1.2b
Using investigative approaches: selecting and managing variables
Recognise the range of variables involved in an investigation and decide which to control.
7Ed, 7Ee
1.2c
Using investigative approaches: assessing risk and working safely
Explain how action has been taken to control obvious risk and how methods are adequate for the task.
7Ea, 7Eb, 7Ec
7Ed, 7Ee
1.2d
Using investigative approaches: obtaining and presenting primary evidence
Describe and record observations and evidence systematically.
7Eb, 7Ec, 7Ed
7Ee
Recognise that the presentation of experimental results through the routine use of tables, bar charts and simple graphs makes it easier to see patterns and trends.
7Eb, 7Ed, 7Ee
1.2e
Working critically with primary evidence
Describe patterns and trends in results and link this evidence to any prediction made.
7Ec, 7Ed, 7Ee
Describe and suggest how planning and implementation could be improved
7Ed, 7Ee
1.2f
Working critically with secondary evidence
Describe patterns and trends in secondary evidence and link these to the prediction or conclusion drawn.
7Ea, 7Eb, 7Ee
Recognise that different conclusions may be drawn from secondary data.
7Eb, 7Ec
Code
Framework sub-strands
Year 7
Topic
3.2
Chemical reactions
Sort some reactions into reversible and irreversible.
7Ee
Recognise that new materials are made during chemical reactions.
7Ee
3.3
Patterns in chemical reactions
Describe, record and group observations from chemical reactions.
7Ea, 7Ec, 7Ed
7Ee
Topic
Level
Learning objectives covered
Key words
Tasks
7Ea
Must
All pupils must: realise that acids can be hazardous; work safely with dilute acids; be able to deal with acids and alkalis if they are splashed on the skin; describe some hazard warnings used on laboratory chemicals and road tankers.
acid, alkali
Starter 1, Starter 3, Starter 5, Explaining 1, Exploring 3, Plenary 2, Homework 1
Should
Most pupils should: describe what is mean by a risk assessment; identify the hazard warning symbols
for corrosive and irritant substances; describe how dilution with water can reduce the hazard of an
acid or alkali; give the names of the three common laboratory acids: sulphuric acid, nitric acid and
hydrochloric acid; give some examples of the uses of acids; use the Hazchem code to identify the
hazards of chemicals.
corrosive, hydrochloric acid, irritant, nitric acid, risk assessment, sulphuric acid
Starter 1, Starter 2, Explaining 1, Starter 5, Exploring 3, Plenary 1, Homework 1
Could
Some pupils could: describe in detail how the Hazchem code is used by the emergency services.
Starter 1, Starter 2, Explaining 1, Starter 5, Exploring 3, Plenary 1, Homework 2
7Eb
Must
All pupils must: state that acids have a sour or sharp taste.
acid
Starter 2, Exploring 4, Exploring 2, Explaining 1, Explaining 2, Plenary 1, Homework 1
Should
Most pupils should: state that vinegar and citrus fruits are acidic; identify some everyday uses of acids,
for example in preserving foods; describe how some acids used in the home are less hazardous than
those used in laboratories.
Starter 1, Starter 2, Exploring 4, Exploring 2, Explaining 1, Explaining 2, Plenary 2, Plenary 3, Homework 1
Could
Some pupils could: carry out detailed research into the positive and negative effects of acids in the home and in the environment.
Starter 2, Exploring 5, Exploring 3, Explaining 1, Explaining 3, Exploring 1, Plenary 3, Exploring 5 (as homework)
7Ec
Must
All pupils must: describe the colour change of litmus indicator with different substances; explain that alkalis have the opposite effect on indicators from acids; describe substances which are neither acidic nor alkaline as neutral; develop skills in the use of a pestle and mortar, and filtration techniques.
acid, alkali, indicator, litmus, neutral
Starter 1, Explaining 1, Exploring 1, Explaining 2, Plenary 1, Homework 1
Should
Most pupils should: state that most indicators are derived from plant colours; critically evaluate the results of experiments with indicators; explain that the neutral (purple) form of litmus is a mixture of the red and blue forms; state that alkalis are at least as corrosive as acids.
Starter 1, Starter 2, Explaining 1, Exploring 1, Explaining 2, Plenary 3, Homework 1
Could
Some pupils could: explain the role of Arabic scientists in developing the concept of an alkali.
Starter 1, Explaining 1, Exploring 1, Explaining 2, Plenary 3, Plenary 4, Homework 1
7Ed
Must
All pupils must: use universal indicator to test solutions for acidity and alkalinity and to measure pH;
give examples of everyday substances that are acids or alkalis.
pH
Starter 1, Starter 2, Exploring 2, Explaining 2, Plenary 1, Homework 1
Should
Most pupils should: explain that in the past there were a number of competing theories to explain acidity; describe the main features of the pH scale and classify solutions as strong or weak acids or alkalis; identify the pH of a solution using universal indicator.
strong/weak (as applied to acids), universal indicator
Starter 1, Starter 2, Exploring 1, Exploring 2, Explaining 2, Plenary 2, Homework 2
Could
Some pupils could: explain that all acids contain hydrogen; use ideas about colour mixing to explain how universal indicators are made, and how they work; describe some alternative theories to explain acidity and explain some evidence for the currently accepted theory.
Starter 2, Exploring 1, Exploring 3, Exploring 4, Explaining 2, Plenary 2, Homework 3
7Ee
Must
All pupils must: explain that a neutral solution can be obtained by adding an acid to an alkali;
recognise that the building of a chemical factory may cause controversy.
Starter 2, Exploring 1, Explaining 1, Plenary 2, Homework 2
Should
Most pupils should: describe pH changes on neutralisation or dilution of an acid or an alkali; link the strength of acids and alkalis to the potential hazards; describe some applications of neutralisation reactions; be able to state some arguments for and against the building of chemical factories.
neutralisation
Starter 1, Exploring 1, Explaining 1, Explaining 3, Plenary 1, Homework 1
Could
Some pupils could: give a balanced evaluation of the arguments for and against the construction of new chemical facilities.
Starter 1, Starter 2, Exploring 4, Explaining 3, Plenary 2, Exploring 2 (as homework)
Task
Level
NC
Type
Objectives
Skills
1 KC
2 KP
3 RC
4 CO
Starter 1
S
46
Classwork
PLTS (Rl, Ct)
2c
Starter 2
S
56
Classwork
1, 5
PLTS (Ct)
1a
1c
2c
a
Exploring 1
M/S
45
Practical
1
PLTS (Ep)
1a
1a, 1c, 2a
2c
a, f
Exploring 2
C
56
Classwork
1, 3, 5
Lit (EC), PLTS (Rl)
2b
2c
Exploring 3
S
46
Classwork
1, 2, 4, 5
ICT (MS
1a, 1b
3a
2c
Exploring 4
C
47
Practical
1, 3
PLTS (Ep, Tw),
Num (M), Lit (EW)
1b
1a, 1b, 1c, 2a
2c
a, c
Exploring 5
M/S
46
Classwork
1, 5
Lit (WF)
2c
Explaining 1
M/S
46
Classwork
1, 3, 5
2c
c
Explaining 2
C
57
Practical
1
Num (L)
1a
1c,
2c
a
Explaining 3
M/S
46
Classwork
2, 6, 7
Lit (DS)
2a, 2b
3a
4c
a, c, d, j
Plenary 1
S
46
Classwork
all topics
PLTS (Rl)
2c
Plenary 2
M/S
45
Classwork
1, 3, 5,
Lit (WF)
2c
Plenary 3
C
57
Classwork
2, 6, 7
Lit (EW), PLTS (Ep)
2a, 2b, 4a
4c
a, c, d, e, j
Plenary 4
M/S
47
Classwork
2, 6, 7
Lit (EW)
2a, 2b, 4a
4c
c, d, j, k
Plenary 5
M/S
46
Classwork
whole unit
PLTS (Rl)
2c
Plenary 6
M/S
46
Classwork
whole unit
PLTS (Rl)
2c
Plenary 7
M/S
47
Classwork
whole unit
PLTS (Rl, Sm)
Homework 1
S/C
46
Homework
1, 5
1a
1a, 1b, 2a
2c
c
Homework 2
S
46
Homework/ Practical
1, 5
PLTS (Ie)
1a
1a, 1b, 1c, 2a, 2b, 3a
2c
a, c
This unit introduces ideas about acids, alkalis and indicators
in the context of acid manufacture. There is also an introduction to ideas about risk assessment and hazard classification.
We recommend between 7.5 and 10 hours of teaching time for this unit.
(L4) Recognise that people who deal with acids or alkalis have strict
safety rules.
SHOULD
2 Yr KS3
PB pages
7476
7Ee Starter 1
7Ee Exploring 1
7Ee Explaining 1
7Ee Explaining 3
7Ee Exploring 2
7Ee Plenary 1 (as
homework)
7Ee Plenary 7
Most pupils should:
(L5) Describe some of the arguments for and against industrial development in a particular area.
(L6) Recognise that the modern understanding of acids and alkalis
is based on work from many scientists, including Arabic scientists.
From KS2 most pupils will:
know that solids remain in the solution when they dissolve
know that there is a limit to how much solid will dissolve in a liquid
know about several variables which affect the rate at which a solid will dissolve
know that some materials can be dangerous.
This unit builds on ideas introduced in the QCA Scheme of Work
for KS2: Unit 6C More about dissolving and Unit 6D Reversible and irreversible changes.
Some pupils could:
(L7) Evaluate the conflicting evidence for competing theories about acids.
(L7) Give reasons for why you agree or disagree with others when
discussing the arguments for and against industrial development in an area.
Key processes
At the end of this unit
All pupils must:
(L4) Carry out a fair test.
(L4) Present results in table and bar charts. (L5) Work safely with dilute acids and alkalis.
(L5) Use an indicator to work out if something is acidic, alkaline or
neutral.
The linking theme for this unit is the manufacture, transportation
and uses of acids. The manufacture of sulphuric acid is used to
show how hazards are classified, the care needed in transportation and storage of chemicals and the need to monitor the environment. The uses of weak acids are introduced through the familiar context
of food and drink. The aim throughout is to build up the more abstract ideas from contexts, applications or ideas with which the pupils are already confident, or where the relevance should be readily apparent.
Most pupils should:
(L5) Use a knowledge of acids and alkalis to identify questions that can be investigated and suggest appropriate data to collect.
(L5) Identify relationships in data.
(L6) Recognise hazard warning symbols and act accordingly (maybe using secondary sources to find out the dangers).
(L6) Describe how to lessen the risks of working with acids and alkalis.
(L6) Explain how conclusions match evidence. (L6) Suggest how a method can be improved.
Some pupils could:
(L7) Evaluate your own work and that of others to see whether you can make valid comparisons between the different sets of results.
Topic 7Ea uses the manufacture and transport of acids to
introduce ideas about hazard warning classifications as used in the laboratory and for the transportation of chemicals.
Topic 7Eb introduces the idea that many familiar and non- hazardous substances are classified as acids, and that these non- hazardous acids can be identified by their taste.
Topic 7Ec introduces acids and alkalis with a practical definition based on their effect on indicators. The practical and historical approach is sustained through the introduction to alkalis.
Topic 7Ed progresses from this concrete experience of acids and alkalis to the more theoretical concepts of pH, substance classification and acid strength, by looking at how our understanding of the nature of acids has changed over time. In
both Topics 7Ec and 7Ed, familiar substances encountered in the home are used as a context to introduce new scientific ideas. Practical work covers ideas about blind testing in an investigation where only subjective results can be obtained.
Topic 7Ee looks at some applications of neutralisation in more detail, and includes investigations of the way that pH changes when an acid is added to an alkali. Pupils can apply their ideas on neutralisation to a practical homework on making sherbet, giving a return to the theme of food and drink. There is also the
opportunity for pupils to carry out an investigation for Attainment Target 1 to find out which of a range of indigestion cures is most effective. The topic ends with a look at why manufacturing plants are situated in particular areas, offering pupils the chance to engage in debate about the possible impact of a development in their local area.
Range and content
At the end of this unit
All pupils must:
(W4) Name something that is an acid.
(L4) Describe differences between acids and alkalis. (L4) List some common uses of acids and alkalis.
Most pupils should:
(L5) Be able to classify solutions as acidic, alkaline or neutral using indicator colours and pH values.
(L6) Explain what happens to pH during neutralisation. (L6) List some common uses of neutralisation.
Some pupils could:
(L7) Link the pH of an acid or alkali to its hazards.
For a list of updated and vetted websites that can be used to
support your teaching of this unit please visit the Exploring Science: How Science Works E-Forum HYPERLINK http://groups.google.co.uk/group/exploringscience (http://groups.google.co.uk/group/exploringscience).
Expectations
Key concepts
At the end of this unit
All pupils must:
(L4) Recognise that different people will have different views on the development of an industrial site.
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Acids and alkalis
7E
7E NC statements covered
From KS2
4 Curriculum opportunities
COULD
PB pages
7476
Starter 1
Starter 2
Exploring 4
Explaining 3
Plenary 2
Exploring 2 (as
homework)
At KS3
1 Key concepts
2 Key processes
Skills opportunities for Personal, Learning and Thinking Skills (PLTS),
literacy, numeracy and ICT are included in the individual topic notes.
3 Range and content
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7EAcids and alkalis
Framework statements covered by Unit 7E
1 How Science Works
1.1 Explanations, arguments and decisions
SHOULD
PB pages
7476
Starter 1
Exploring 1
Explaining 1
Explaining 3
Plenary 1
Plenary 7
Homework 1
1.2 Practical and enquiry skills
3 Chemical and material behaviour
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7E Routes through the unit
This page suggests routes through the unit at three different levels, using some of the tasks provided. Many other teaching sequences are possible using the alternative teaching materials and tasks provided or
by adding your own materials. We recommend between 7.5 and 10 hours of teaching time for this unit.
Acids and alkalis
7E
MUST
PB pages
7476
Starter 2
Exploring 1
Explaining 1
Plenary 2
Plenary 7
Homework 2
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7EAcids and alkalis
7E Background information
7Ea Acids in action/Diamonds are for safety
Many acids and alkalis are classified as either irritant or corrosive depending on the concentration. This means that appropriate care must be taken when handling them.
and accurate at this level, with power having the dual meaning
of strength as well as its mathematical sense as in power of ten. The recognition that hydrogen was the distinguishing feature of
an acid was a far from obvious one, and to this day we have the reminder of the erroneous theory that oxygen (= acid maker) was the relevant element. The fact that these theories of acid behaviour were being developed at the same time as the oxygen/phlogiston debate was at its height means that these theories are intimately intertwined.
Number and title
Level
Location
Type
Tasks
Finding the balance
Must/Should
PB p7475
Classwork
Explaining 1
Not in my back yard?
Must/Should
PB p76
Classwork
Explaining 3
7E
Quick Quiz
Must/Should
ASP
Classwork
Plenary 5
7E
Quick Quiz Answer Sheet
Must/Should
ASP
Classwork
Plenary 5
7E
End of Unit Test
Must/Should
ASP
Classwork
Plenary 6
7E
Level Ladder
Must/Should
ASP
Classwork
Plenary 7
7Ee
Quick Check
Must/Should
ASP
Classwork
Plenary 1
7Ee
Word Sheet
Should
ASP
Homework
7Ee(1)
Finding the balance
Must
CHAP
Access
Explaining 1
7Ee(2)
Rainbow fizz
Must/Should
CHAP
Practical
Exploring 1
7Ee(3)
Rainbow fizz results sheet
Must
CHAP
Practical
Exploring 1
7Ee(4)
Indigestion 1
Must/Should
CHAP
Practical
Exploring 4
7Ee(5)
Indigestion 2
Should
CHAP
Classwork
Exploring 2
7Ee(6)
Reverseword
Must/should
CHAP
Classwork
Exploring 5
7Ee(7)
Where do you build it?
Must/Should
CHAP
Classwork
Plenary 4
7Ee(8)
Making sherbet 1
Must/Should
CHAP
Homework
Homework 1
7Ee(9)
Making sherbet 2
Must/Should
CHAP
Homework
Homework 2
This is usually done by consulting and, if necessary, adapting
model standard risk assessments provided by employers. In most instances this will be information provided by organisations such as CLEAPSS or the ASE.
Principles of risk management include:
The description universal indicators is used deliberately to try to
counteract the idea that there is one substance called Universal Indicator. Universal (or full range) indicators are a class of mixtures which are made from blends of individual indicators. The type
used in schools has the majority of its colour changes in the pH
range 411: it is therefore well suited to classifying substances on
a five-point descriptive scale (strong acid/weak acid/neutral/weak alkali/strong alkali). For more specialised purposes (e.g. soil testing)
a narrow range indicator may be appropriate, e.g. with five or six distinct colours within the range pH 5.0 to 8.0.
consideration of whether a safer alternative substance or
procedure may be substituted
reducing the amount of hazardous substance used, for
example by reducing the scale of an experiment or using a less concentrated solution
taking appropriate precautions, e.g. use of fume cupboards, eye protection.
A common error by pupils and others is to assume that because
acids are dangerous, alkalis are safe. In fact, for solutions of equal concentration, alkalis are usually more dangerous than acids.
7Ee Finding the balance/Not in my backyard?
The precise definition of pH is - log [H+], where [H+] is the
hydrogen ion concentration in moles per cubic decimetre. The product of the hydrogen ion and hydroxide ion concentrations
is about 10-14 at 25 C. At the neutral point the hydrogen and hydroxide ion concentrations are equal at 10-7 (hence pH 7 is neutral). While even the highest-attaining pupils will not need anything like this depth of treatment, the main implications for the teaching at this level are that:
Further reading
A more extended treatment of the acid bath murders is given in
Richard Hart Chemistry Matters, pages 208209 (OUP, 1978).
7Eb Tangy tastes
The definition of an acid has changed over time. The accepted definition that is most useful for KS3 teachers is that acids are substances which dissolve in water to give solutions containing hydrogen ions (H+). The development of these ideas is taken further in Topic 7Ed.
the choice of the numbers 1 to 14 is not random some more
enquiring pupils may be satisfied with the explanation that it is linked in some way to the amount of hydrogen
changing the dilution of an acid or alkali by a factor of ten will alter the pH by one unit (this is the effect of choosing a logarithmic scale)
addition of a small amount of acid or alkali near the neutral point can have quite a large effect on the pH, whereas adding the same amount to a strong acid or alkali will have very little effect.
The sharp taste of acids is used as a starting point for identifying
acids in this topic. The English word sour derives from the same root as the German sauer meaning acid (as in sauerkraut).
7Ec In the red/Making an ash of it
Indicators are themselves weak acids or bases, which can gain
or lose hydrogen ions depending on the pH of the solution. This change in structure also causes a change in colour. The precise pH
at which this colour change occurs varies from indicator to indicator. Most indicators have two main colours, and an intermediate
colour which is the result of colour mixing. For example, the purple colour of neutral litmus solution is a result of a mixture of equal concentrations of the red (acidic) and blue (alkaline) forms. Litmus changes colour at about pH 7 and is therefore particularly well
suited to elementary work.
When fuels based on plant materials are burned, the non-metals
oxidise to volatile oxides. The solid ash left at the end of the fire will consist of the metal oxides mainly potassium and magnesium,
which were originally absorbed by the plant from the soil. These oxides are alkaline in nature, and the Pupils Book emphasises the
link between the original discovery of this property and our current use of the word alkali. It is also the source of the symbol K for potassium the first letter of the name Kali in Arabic, or the Latin equivalent Kalium (it is also Kalion in Greek). The reaction of alkalis with fats and oils to make soap is also considered. This is one
reason why concentrated alkalis are so corrosive: they start to react with the natural oils in your skin to turn them into soap.
7Ed Mixing a rainbow/Focus on the H factor
The strength of acids and alkalis is linked to the concentration of hydrogen ions in solution. Although the origin of the phrase is Danish (potenz, meaning power in Danish and German) the use
of power of hydrogen to explain the meaning of pH is logical
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edition
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Task
Level
NC
Type
Objectives
Skills
1 KC
2 KP
3 RC
4 CO
Starter 1
M/S
45
Classwork
PLTS (Ct, Rl)
2c
Starter 2
S
45
Classwork
5, 7
PLTS (Ct)
1a
1a
2c
a
Exploring 1
M/S
35
Practical
1, 2, 4, 5
PLTS (Ep, Tw)
1a, 1b, 2a
2c
Exploring 2
M/S
35
Classwork
1, 2, 4, 5
2a
2c
Exploring 3
C
46
Practical
1, 4, 5
PLTS (Ep, Tw)
1a
1a, 1c, 2a
2c
a
Exploring 4
S
45
Classwork
1, 4, 5
PLTS (Ct)
2c,
a
Exploring 5
S/C
56
Practical
1, 4, 5, 7
PLTS (Ct)
1a
1a, 1c, 2a, 2b
2c
a, f
Exploring 6
S/C
57
Classwork
3, 6,
Lit (EC), PLTS (Tw, Ep)
1b, 3a
2c
h
Explaining 1
S/C
57
Classwork
1, 2, 4, 5
PLTS (Rl)
2a
2c
b, c
Explaining 2
M/S
45
Classwork
3, 6, 8
3a
2c
h
Plenary 1
S
46
Classwork
1, 2, 4, 5
PLTS (Ct, Rl)
2c
Plenary 2
S
46
Classwork
1, 2, 4, 5
PLTS (Ct)
2c
Plenary 3
M
45
Classwork
1, 2, 4, 5
Lit (WF)
2c
Homework 1
M
4
Homework
1, 2, 4
2c
c
Homework 2
S
56
Homework
7
PLTS (Ct)
1a, 1b
2a
2c
Homework 3
C
58
Homework
6
Lit (Ew)
1c
2c
b, c
COULD
PB pages
7073
Starter 2
Exploring 1
Exploring 3
Exploring 4
Explaining 2
Plenary 2
Homework 3
MUST
PB pages
7073
Starter 1
Starter 2
Exploring 2
Explaining 2
Plenary 1
Homework 1
SHOULD
2 Yr KS3*
PB pages
6873
7Ec Starter 1
7Ec Exploring 2
7Ec Explaining 1
7Ec Explaining 2
7Ed Explaining 1
7Ed Exploring 1
7Ed Plenary 2
7Ed Homework 2
SHOULD
PB pages
7073
Starter 1
Starter 2
Exploring 1
Exploring 2
Explaining 2
Plenary 2
Homework 2
Pupils materials
Number and title
Level
Location
Type
Tasks
Mixing a rainbow
Must/Should
PB p7071
Classwork
Explaining 1
What is an acid?
Should/Could
PB p7273
Classwork
Explaining 2
7Ed
Quick Check
Must/Should
ASP
Classwork
Plenary 1
7Ed
Word Sheet
Must/Should
ASP
Homework
7Ed(1)
Mixing a rainbow
Must
CHAP
Access
Explaining 1
7Ed(2)
The H factor
Must/Should
CHAP
Access
Explaining 2
7Ed(3)
pH testing 1
Must
CHAP
Practical
Exploring 1
7Ed(4)
pH testing 2
Should
CHAP
Practical
Exploring 1
7Ed(5)
Arguments about acids 1
Should
CHAP
Classwork
Exploring 6
7Ed(6)
Arguments about acids 2
Could
CHAP
Classwork
Exploring 6
7Ed(7)
Making a pH chart
Must
CHAP
Homework
Homework 1
7Ed(8)
More about indicators
Should
CHAP
Homework
Homework 2
7Ed(9)
pH balanced products
Could
CHAP
Homework
Homework 3
SS14
Thinking Skills
Should
CHAP
Skills Sheet
Exploring 4, Plenary 2
Objectives
All pupils must:
(1) realise that acids can be hazardous
(2) work safely with dilute acids
(3) be able to deal with acids and alkalis if they are splashed on the skin
(4) describe some hazard warnings used on laboratory chemicals and road tankers.
Correctly use the words acid, alkali.
Most pupils should:
(5) describe what is mean by a risk assessment
(6) identify the hazard warning symbols for corrosive and irritant substances
(7) describe how dilution with water can reduce the hazard of an acid or alkali
(8) give the names of the three common laboratory acids:
sulphuric acid, nitric acid and hydrochloric acid
(9) give some examples of the uses of acids
(10) use the Hazchem code to identify the hazards of chemicals.
Correctly use the words corrosive, hydrochloric acid,
irritant, nitric acid, risk assessment, sulphuric acid.
Some pupils could:
(11) describe in detail how the Hazchem code is used by the emergency services.
Exemplar topic plans
* This table is repeated in 7Eb.
Topic notes
Targets for the topic can be accessed via the ActiveBook or
ActiveTeach from the link next to the initiator question.
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7EaAcids in action
Topic task planner
Use these tasks to adapt the exemplar topic plan to your own needs. Many tasks can be adapted to become different types (e.g. starter
rather than exploring). AT or AB/AT at the top of a task means that the task depends on using the ActiveBook and/or ActiveTeach;
where these symbols appear in brackets it indicates that the task can be carried out with or without their use.
Task
Level
NC
Type
Objectives
Skills
1 KC
2 KP
3 RC
4 CO
Starter 1
S
46
Practical
1
PLTS (Ct)
1a
1a
2c
a
Starter 2
All
Classwork
2
PLTS (Rl)
2c
Exploring 1
M/S
45
Practical
26
PLTS (Ep, Tw)
1b
1a, 1b, 2a,
2c
a
Exploring 2
M/S
45
Classwork
1, 2, 3, 6, 7
PLTS (Ep)
1b
2a
2c
Exploring 3
All
46
Classwork
6
PLTS (Ct)
1b
2a, 2b
2c
Explaining 1
S
45
Classwork
1, 2, 3
1b
2c
Explaining 2
S
45
Classwork
1, 2, 3, 5, 6, 7
3a
2c
h
Plenary 1
M
45
Classwork
1, 5
Lit (WF)
2c
Plenary 2
M
45
Classwork
2, 3, 6, 7
Lit (WF)
2c
Plenary 3
M/S
45
Classwork
13, 8
Lit (WF), PLTS (Ct, Rl)
2c
Plenary 4
All
45
Classwork
13, 58
PLTS (Ct)
2c
Homework 1
All
45
Homework
13, 68
PLTS (Ie)
1a, 1b
1a, 1b, 1c,
2a, 2b
2c
a, c, e
Homework 2
S/C
46
Homework
13, 68
Lit (RR), ICT (PS), PLTS (Tw)
2a, 3a
2c
a, c
is likely to be written off) about one third to one half full with
granulated sugar. Pour concentrated sulphuric acid over it so that
it just covers the sugar. The sugar will darken immediately. Stir the mixture carefully and leave it to stand the reaction will become more vigorous after about a minute. Black carbon is formed, and the reaction is sufficiently exothermic to turn the water that is
formed into steam, which pushes the sugar up out of the beaker in
a black, sausage-shaped foam, which then hardens.
Starters
1: Quick Quiz
Afl
Use the 7E Quick Quiz for baseline assessment for this unit.
Pupils could record their answers on the 7E Quick Quiz Answer
Sheet.
2: Acids brainstorm
Ask pupils to brainstorm hazards associated with acids and other chemicals. Draw up a list of key words on the board and save them
to be returned to later in the topic or unit.
Paper towels placed in a beaker of concentrated sulphuric acid will
blacken very quickly the beaker will get warm. You could also demonstrate the action of acid on cotton.
This demonstration should be carried out in a fume cupboard because of the production of carbon monoxide (extremely flammable and toxic) and sulphur dioxide (toxic)
as possible by-products in the reaction. Concentrated sulphuric acid is corrosive.
3: Hazard symbols AT
The second AT presentation link on page 64 opens Hazard warning labels. Ask pupils to match the symbol to the hazard,
or rank the hazards in order from least to most harmful. Use this to stimulate a discussion on whether a flammable substance is more or less harmful than, say, a toxic one. This could also lead to discussion on why different acids and alkalis have different hazard labels, and suitable safety procedures for working with them (e.g.
eye protection).
Resources
Jam jar or 250 cm3 beaker; granulated sugar; concentrated sulphuric acid (corrosive); glass rod; fume cupboard. Optional: paper towels; piece of cotton material.
4: Uses of sulphuric acid AT
Ask pupils to think about why we need to make sulphuric acid. The AT video link on page 63 opens Chemical plants introducing the health and safety officer and his role at the plant together with a summary of what the plant produces and the key uses. Ask pupils
to recall the key points about safety from what they have seen.
Exploring tasks
1: What hazard? AT
The AT animation link on page 65 opens How dangerous are these acids? photos of a number of different acids at varying concentrations. By hovering over the relevant acid, the associated
hazard symbol (corrosive, irritant or low hazard) appears. Pupils can deduce how concentration affects hazard classification and compare the hazards posed by different acids.
5: Demonstration: Action of concentrated sulphuric acid
This is a spectacular demonstration of the effect of a corrosive substance on everyday materials. Fill a beaker (or jam jar it
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Acids in action7Ea
2: Thinking about dilution (AT)
PMI: only dilute acids should be allowed. (Possible answers:
P the hazards of concentrated acids would be removed, murderers would not be able to dissolve bodies!; M it would be much more expensive to transport acids; I are some concentrated acids more dangerous than others?)
The first AT presentation link on page 65 opens Thinking about dilution a PowerPoint presentation version of this task.
For pupils who might find it difficult to cope with the question in
this open-ended form, you could present several graph types and ask them to discuss which would best match the statement.
2: Pupils Book page 6465 (AB/AT)
Worksheet 7Ea(1) is the Access Sheet.
COULD
PB pages
6869
Starter 1
Explaining 1
Exploring 1
Explaining 2
Plenary 3
Plenary 4
Homework 1
The AT video link on page 65 opens the video Dealing with
hazards this shows how safety officers deal with spillages within
a factory.
3: Practical: Comparing acids
Pupils compare the hazardous nature of different acids by reference to simple observations linked to chemical reactivity.
The third AT presentation link and the document link on page
64 open Handling acids which prompt pupils to design a presentation poster about handling acids safely.
Must: only three acids are used, and the tests are restricted to
those that can give a clear visual indication. The instructions are on Worksheet 7Ea(2).
Should: instructions are given on Worksheet 7Ea(3). Pupils use another acid and a more subtle test (the reaction with
sodium hydroxide solution) is introduced. Given the corrosive nature of sodium hydroxide if it is at a concentration likely to give a measurable temperature rise, this version should only be attempted if you are confident of the practical abilities and
behaviour of the group. If digital temperature probes capable of reading to 0.1 C are available, this may allow the concentration of the sodium hydroxide to be reduced to 0.4 mol dm3 (irritant)
while still getting useful and observable results. An alternative would be to set up four temperature probes linked to a datalogger for this part of the experiment, which would then effectively become a demonstration.
Could: present pupils with extracts from the relevant CLEAPSS Student Safety Sheets, and ask them to discuss the risks involved before starting any practical work.
1 mol dm-3 sodium hydroxide is corrosive. Eye protection should
be worn.
3: Comparing the hazards
Worksheet 7Ea(4) asks pupils to use the results of experiments to compare reactions and hazards, and draw conclusions. It also
reinforces pupils knowledge of what a fair test is.
Plenaries
1: Thinking about hazards (AT)
PMI: all chemicals should have hazard labels. (Possible answers:
P it would be more obvious if the chemical is hazardous or not;
M more hazardous chemicals might be less obvious; I who invented the hazard labels? When were these labels introduced?)
The third AT presentation link on page 65 opens Thinking about hazards a PowerPoint presentation version of this task.
2: Hazards matching
Worksheet 7Ea(5) allows pupils to summarise key learning on hazards through a matching activity. This could be developed into
a projected resource and pupils could carry out the matching on screen. As an extension, ask pupils to rank the symbols in order from least to most harmful. There is no one correct answer to this ranking exercise, as the dangers of a particular chemical depend
on its circumstances for instance, something that is poisonous may be completely harmless in the context of a spill, and some flammable substances can be consumed (e.g. alcohol!).
Resources (per group)
Must: test tube rack plus at least 3 test tubes; 3 pieces of magnesium ribbon (about 1 cm length); 3 marble chips (small enough to fit comfortably into the test tube); thermometer; dilute hydrochloric acid at concentrations
1 mol dm-3, 0.1 mol dm-3 and 0.01 mol dm-3 labelled (at random) X, Y and Z; Worksheet 7Ea(2).
Should: as for Must level, plus: hydrochloric and ethanoic acids
at concentrations of 0.5 mol dm-3, 1 mol dm-3 and 2 mol dm-3; sodium hydroxide solution (1 mol dm-3); eye protection;
thermometers or digital temperature probes; Worksheet 7Ea(3).
Resources
Worksheet 7Ea(5); access to glue and scissors.
3: Summarising ideas on hazards
Pupils Book question 6 on page 65 allows pupils to summarise their ideas on hazards.
4: Acid bath murders
Ask pupils to find out more about the acid bath murders and present their findings in the form of a presentation to the rest of the class.
4: I can cloze exercise AB/AT
Afl
The second AT document link on page 65 opens a cloze
exercise covering the material on pages 6465. There is also an AT
presentation version with answers.
Resources
Library/internet access.
5: Quick Check
5: Acid spills AB/AT
The first AT document link on page 65 opens Acid spills a document that can be used as a stimulus to get pupils thinking about what would happen if a there were an accident in the
locality. If there is a genuine local incident that can be drawn upon through local news reports this would obviously add immediate
interest. This could then link to Homework 2.
Afl
The Quick Check sheet for this topic asks pupils to use their
experience of laboratory work at KS2 and from this topic to identify
safety hazards in the laboratory through a cartoon of unsafe practices.
Homework tasks
1: Worksheet 7Ea(6) is a write-on sheet on the Hazchem code.
2: Worksheet 7Ea(7) contains more complex questions on the
Hazchem code.
3: Question 7 on page 65 of the Pupils Book could be used as a homework task in extended writing.
Explaining tasks
1: Pupils Book page 63
Question 3 encourages pupils to think about translating a comparative statement into graphical form. A graph with a positive
correlation would be expected if the statement were true.
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Starter 1
Explaining 1
Exploring 1
Explaining 2
Plenary 1
Homework 1
SHOULD
2 Yr KS3*
PB pages
6873
7Ec Starter 1
7Ec Exploring 2
7Ec Explaining 1
7Ec Explaining 2
7Ed Explaining 1
7Ed Exploring 1
7Ed Plenary 2
7Ed Homework 2
SHOULD
PB pages
6869
Starter 1
Starter 2
Explaining 1
Exploring 1
Explaining 2
Plenary 3
Homework 1
Number and title
Level
Location
Type
Tasks
In the red
Must/Should
PB p68
Classwork
Explaining 1
Making an ash of it
Must/Should
PB p69
Classwork
Explaining 2
7Ec
Quick Check
Must
ASP
Classwork
Plenary 3
7Eb
Word Sheet
Must
ASP
Homework
7Ec(1)
In the red
Must
CHAP
Access
Explaining 1
7Ec(2)
Making an ash of it
Must
CHAP
Access
Explaining 2
7Ec(3)
Red cabbage indicator
Must/Should
CHAP
Practical
Exploring 1
7Ec(4)
Red cabbage: methods and techniques
Must/Should
CHAP
Practical
Exploring 1
7Ec(5)
The litmus test 1
Must/should
CHAP
Classwork
Exploring 3
7Ec(6)
The litmus test 2
Must
CHAP
Classwork
Exploring 3
7Ec(7)
Indicators at home 1
Must
CHAP
Homework
Homework 1
7Ec(8)
Indicators at home 2
Should
CHAP
Homework
Homework 1
7Ec(9)
Alkalis in action
Could
CHAP
Classwork
Homework 2
SS12
Thinking Skills
All
CHAP
Skills Sheet
Plenary 4
Pupils materials
Task
Level
NC
Type
Objectives
Skills
1 KC
2 KP
3 RC
4 CO
Starter 1
M/S
46
Classwork
15
PLTS (Ep)
2c
a, c
Starter 2
M/S
56
Classwork
15
1b
2c
c, k
Exploring 1
M/S
36
Practical
14
PLTS (Ep, Tw)
1b
1a, 1b, 1c, 2a
2c
c, k
Exploring 2
M/S
Classwork
1, 2, 3
2a
2c
c, k
Exploring 3
M/S
Classwork
1, 3, 4
Lit (WF)
2c
c
Exploring 4
S/C
57
Classwork
5
Num (T,C,L)
1b
2a, 3a
2c
Exploring 5
C
57
Classwork/ Homework
3, 6
Lit (RR), ICT (PS), PLTS (Tw)
3a
2c, 4c
b
Explaining 1
M/S
47
Classwork
3
2c
Explaining 2
M/S
Classwork
2, 3
PLTS (Ct)
2c
c, k
Explaining 3
C
57
Classwork
2c
c, k
Plenary 1
M
45
Classwork
1, 2, 3, 4
Lit (WF)
2c
Plenary 2
M/S
45
Classwork
2
PLTS (Rl)
2c
Plenary 3
M/S
Classwork
14
PLTS (Ct)
3a
2c
Homework 1
All
45
Homework
3, 5
Lit (WF, RR), ICT (PS)
3a
2c
c
Objectives
All pupils must:
(1) state that acids have a sour or sharp taste.
Correctly use the word acid.
Most pupils should:
(2) state that vinegar and citrus fruits are acidic
(3) identify some everyday uses of acids, for example in preserving foods
(4) describe how some acids used in the home are less hazardous than those used in laboratories.
Some pupils could:
(5) carry out detailed research into the positive and negative effects of acids in the home and in the environment.
Exemplar topic plans
Topic notes
Targets for the topic can be accessed via the ActiveBook or
ActiveTeach from the link next to the initiator question.
* This table is repeated in 7Ea
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Tangy tastes7Eb
Topic task planner
Use these tasks to adapt the exemplar topic plans to your own needs. Many tasks can be adapted to become different types (e.g. starter
rather than exploring). AT or AB/AT at the top of a task means that the task depends on using the ActiveBook and/or ActiveTeach;
where these symbols appear in brackets it indicates that the task can be carried out with or without their use. Also consider using one of the plenaries from the previous topic as a starter task in this topic.
SHOULD
2 Yr KS3*
PB pages
6367
7Ea Starter 1
7Ea Starter 4
7Ea Exploring 2
7Ea Exploring 1
7Eb Starter 2
7Eb Exploring 3
7Eb Exploring 2
7Eb Explaining 2
7Eb Plenary 2
7Eb Exploring 5
(as homework)
This experiment is best done in the food technology room
or the dining area. If a laboratory has to be used then the
exceptional nature of this practical should be emphasised. Wipe down all benches and lay out paper towels to create clean areas. All bottles of chemicals must be removed from the laboratory beforehand.
Starters
1: Acids discussion
Ask pupils to discuss the statement All acids are dangerous.
Collect ideas or take a vote. This could be revisited later in the topic.
2: Acid sampling
Ask for a brave volunteer who is prepared to sample an acid in front of the class. Reward the volunteer with an acid drop or sherbet lemon sweet, and asked them to describe the taste. If done in a laboratory, take care to ensure that there is no contact
between sweets and surfaces pupils should be reminded that this
is an exception to a general rule. This could then lead in to a more general discussion about foods and drinks that contain acids.
Resources (per group or class, depending on
the method used)
Set of clean, disposable plastic drinking cups containing a selection of liquids (vinegar, salt water, tonic water, lemon juice, fizzy orange, milk, sugar water) labelled L1, L2, L3, etc; plastic drinking straws one per pupil per cup; blindfold; Worksheets
7Eb(2) and 7Eb(3).
2: Drink ingredients AT
The second AT presentation link on page 66 of the Pupils Book opens Drink ingredients an activity in which pupils are presented with pictures of ingredients of some popular drinks. Ask pupils to
list the acids they contain.
Exploring tasks
1: Practical: Taste tests
This activity depends on being able to carry out the test under hygienic conditions. Working in pairs or small groups, pupils take
a blind test in which they are asked to describe and identify a number of liquids. The liquids could be stored in plastic drinking cups, and dispensed using the end of a drinking straw (which
is easily disposable if it becomes contaminated). Include some liquids which are acidic, as well as a range of contrasting tastes.
Alternatively, you could dispense the liquids to pupils while they are working on another written task.
3: Acid or not acid? AT
The AT animation link on page 67 of the Pupils Book opens Acid
or not acid? audio files in which young people describe
how certain substances taste. Ask pupils to decide acid or
not acid?
4: Data analysis: Reaction of limestone and acid
Ask pupils to carry out a data analysis on results from an
experiment in which limestone chips are reacted with the acid in a fizzy drink provided on Worksheet 7Eb(4). This activity develops numeracy skills in calculation and graph plotting. Pupils are asked
to analyse critically the results of the experiment and whether conclusions drawn are valid.
Must: pupils use the framework on Worksheet 7Eb(2) to record
their results.
Should: Worksheet 7Eb(3) provides guidance but pupils design their own table for recording results.
Could: Worksheet 7Eb(3) provides an extension activity where pupils explore which areas of the tongue are most sensitive to acids.
5: Investigating applications of acids
Group work task pupils use Worksheet 7Eb(7) as a prompt to help them investigate an aspect of the applications of acids and present the work back to the class. This could also be set as a homework task.
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7EbTangy tastes
Explaining tasks
1: Pupils Book pages 6667
This explains the use of acids in foods and drinks, including coverage of taste, health issues, food preservation and food labelling. Worksheet 7Eb(1) is the Access Sheet. Use photo F on page 67 as a stimulus to discuss the similarities and differences between vinegar and non-brewed condiment.
SHOULD
PB pages
6667
Starter 1
Starter 2
Exploring 4
Exploring 2
Explaining 1
Explaining 2
Plenary 2
Plenary 3
Homework 1
The first AT document link on page 67 opens True or false?
a sequence of sentences for pupils to identify mistakes in.
2: Scurvy
Ask pupils if they know why British sailors used to be known as
limeys. Pupils could discuss their answers and use the information on Pupils Book page 66 to check their understanding.
3: Whats in a name?
Show samples of various vinegars, non-brewed condiment, dilute and concentrated ethanoic acid. Explain that everyday terms are
not the same as scientific ones, and that as the context for our understanding about acids changes, so do the names, e.g. vinegar/ acetic acid/ethanoic acid according to context, and different names historically such as methane carboxylic acid, acetyl hydroxide, hydrogen acetate.
Plenaries
1: I can cloze exercise AB/AT
Afl
The second AT document link on page 67 opens a cloze
exercise covering the content of pages 6667. There is also an AT
presentation version with answers.
2: Quick Check
The Quick Check sheet requires pupils to use a selection of letters to come up with the names of a number of acids studied in this topic.
3: Thinking about acids around us (AT)
OOO: water, vinegar, orange juice. (Possible answers: water is the only neutral substance or not an acid.)
PMI: no substances should be acids. (Possible answers: P
we would not be harmed by acids; M alkalis could not be neutralised, foods would go off more easily, things would taste boring; I how would our stomachs kill harmful bacteria?)
The second AT presentation link on page 67 opens Thinking about acids around us a PowerPoint presentation version of this task.
Homework tasks
1: Pupils find out which products in their homes are acids and
display their results in an appropriate format.
Must: Worksheet 7Eb(5) is a very structured worksheet which requires very simple responses.
Should: Worksheet 7Eb(6) provides structured advice on what
to look for, but a more open-ended choice of materials and formats.
Could: Worksheet 7Eb(7) pupils work in groups and coordinate their research so that each group member has a specific role and/or has responsibility for a particular content area (see also Exploring 6).
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MUST
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Starter 2
Exploring 4
Exploring 2
Explaining 1
Explaining 2
Plenary 1
Homework 1
COULD
PB pages
6667
Starter 2
Exploring 5
Exploring 3
Explaining 1
Explaining 3
Exploring 1
Plenary 3
Exploring 5 (as
homework)
Number and title
Level
Location
Type
Tasks
Tangy tastes
Must/Should
PB p6667
Classwork
Explaining 1
7Eb
Quick Check
Must/Should
ASP
Classwork
Plenary 2
7Eb
Word Sheet
Must/Should
ASP
Homework
7Eb(1)
Tangy tastes
Must
CHAP
Access
Explaining 1
7Eb(2)
Taste tests 1
Must
CHAP
Practical
Exploring 1
7Eb(3)
Taste tests 2
Should/Could
CHAP
Practical
Exploring 1
7Eb(4)
Acid corrosion
Should/Could
CHAP
Classwork
Exploring 4
7Eb(5)
Acids all around 1
Must
CHAP
Homework
Homework 1
7Eb(6)
Acids all around 2
Should
CHAP
Homework
Homework 1
7Eb(7)
Acids all around 3
Could
CHAP
Homework
Exploring 5, Homework 1
SS12
Thinking Skills
Must/Should
CHAP
Skills Sheet
Plenary 3
Task
Level
NC
Type
Objectives
Skills
1 KC
2 KP
3 RC
4 CO
Starter 1
All
46
Classwork
1, 4, 6, 7
PLTS (Rl)
2c
Starter 2
M
46
Classwork
1
PLTS (Ep, Rl)
1b
2c
Starter 3
S
56
Classwork
1, 2, 3, 4, 6, 10
PLTS (Ep), Lit (WF)
1b
2c
Starter 4
S
Classwork
1, 4, 5, 6, 10
PLTS (Ep)
1b
2c
c, e, i
Starter 5
M/S
Practical
1, 2, 6, 8, 9
1b
1a, 1b
2c
Exploring 1
S
5
Classwork
4, 6
1b, 2a
2c
Exploring 2
S
57
Classwork
1, 2, 3, 7
PLTS (Ct)
1b
2c
f
Exploring 3
M/S
47
Practical
19
PLTS (Ep, Tw)
1b
1a, 1b,
1c, 2a
2c
a
Exploring 4
C
57
Homework
1
Lit (RR), ICT (PS), PLTS (Sm)
2a, 3a
2c
a, b
Exploring 5
S
47
Classwork
17, 10, 11
Lit (EC)
1b, 3a
2c
c, d
Explaining 1
M/S
46
Classwork
110
3a
2b
2c
c, e
Explaining 2
M/S
46
Classwork
1, 2, 4, 5, 6, 7, 10, 11
1b,
2c
c, d, e, j
Explaining 3
C
46
Classwork
1
2a
2c
Plenary 1
M/S
Classwork
1, 4, 5
PLTS (Ct)
2c
Plenary 2
M
45
Classwork
1, 4, 5
Lit (WF)
1b
2c
Plenary 3
S
Classwork
19
Lit (RR), ICT (PS), PLTS (Tw, Rl)
1b
2c
Plenary 4
M
45
Classwork
1, 2, 4, 7
PLTS (Rl), Lit (WF)
2c
Plenary 5
M/S
Classwork
1, 2, 3, 5
PLTS (Rl)
1b
2c
Homework 1
M/S
45
Homework
1, 4, 7, 10
Lit (EC)
1b
2c
c
Homework 2
C
46
Homework
1, 4, 7, 10, 11
Lit (EC)
1b
2c
c
Homework 3
C
56
Homework
1, 4, 5, 7, 10, 11
Lit (EW), PLTS (Ct)
1b, 2a
2c
c
COULD
PB pages
6365
Starter 1
Starter 2
Explaining 1
Starter 5
Exploring 3
Plenary 1
Homework 2
Pupils materials
MUST
PB pages
6365
Starter 1
Starter 3
Starter 5
Explaining 1
Exploring 3
Plenary 2
Homework 1
Objectives
All pupils must:
(1) describe the colour change of litmus indicator with different substances
(2) explain that alkalis have the opposite effect on indicators from acids
(3) describe substances which are neither acidic nor alkaline as neutral
(4) develop skills in the use of a pestle and mortar and filtration techniques.
Correctly use the words acid, alkali, indicator, litmus,
neutral.
Most pupils should:
(5) state that most indicators are derived from plant colours
(6) critically evaluate the results of experiments with indicators
(7) explain that the neutral (purple) form of litmus is a mixture of the red and blue forms
(8) state that alkalis are at least as corrosive as acids.
Some pupils could:
(9) explain the role of Arabic scientists in developing the concept of an alkali.
Exemplar topic plans
* This table is repeated in 7Ed.
Topic notes
Targets for the topic can be accessed via the ActiveBook or
ActiveTeach from the link next to the initiator question.
Be prepared: 7Ec
Exploring 1: red cabbage and/or other coloured substances
(e.g. beetroot, blackberries) needed.
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7EcIn the red
Topic task planner
Use these tasks to adapt the exemplar topic plans to your own needs. Many tasks can be adapted to become different types (e.g. starter
rather than exploring). AT or AB/AT at the top of a task means that the task depends on using the ActiveBook and/or ActiveTeach;
where these symbols appear in brackets it indicates that the task can be carried out with or without their use. Also consider using one of the plenaries from the previous topic as a starter task in this topic.
SHOULD
2 Yr KS3*
PB pages
6367
7Ea Starter 1
7Ea Starter 4
7Ea Exploring 2
7Ea Exploring 1
7Eb Starter 2
7Eb Exploring 3
7Eb Exploring 2
7Eb Explaining 2
7Eb Plenary 2
7Eb Exploring 5
(as homework)
Worksheet 7Ec(4) is a follow-up sheet to revise the key words and
processes from the practical procedure. This could be used in class, or as a homework after the experiment has been completed. An alternative use could be as a starter activity in the next topic to reinforce prior learning.
Starters
1: Water into wine
Use the water into wine trick as a starter demonstration. Pour a beaker of water (in fact dilute sodium hydroxide solution) into an apparently empty beaker (which has a few drops of phenolphthalein indicator at the bottom of the beaker). When the alkaline solution touches the indicator, there is a change from colourless to pink/ purple. Ask pupils to speculate how the effect is achieved. Tell them that they will be able to produce similar colour transformations by
the end of the topic.
The first AT document link on page 68 opens Red Cabbage
Indicator a set of sample results which pupils are asked to add to a table.
Eye protection should be worn. There should be no tasting of food and drink (this is just after a tasting lesson!).
Resources (per group)
Part 1: red cabbage; blackberries or other strongly coloured fruit/vegetable; pestle and mortar; filter paper and funnel; access to kettle; Worksheet 7Ec(3). (If overnight storage is needed: boiling tubes/small conical flask with bung or screw cap (McCartney) bottle.)
Part 2: dropping pipettes; spotting tiles; a variety of common substances e.g. vinegar, salt, sugar, lemonade, toothpaste, lemon juice, flour, Milk of Magnesia, washing powder, scouring powder; coloured extract from part 1; eye protection.
Resources
Beaker/wine glass; dilute sodium hydroxide solution (irritant) (0.1 mol dm3); phenolphthalein indicator (highly flammable).
2: Alkali brainstorm
Ask pupils what they already know about acids, whether they have heard the word alkali before, and how you can tell the difference between acids and alkalis.
Exploring tasks
2: Experiments with litmus AT
The AT animation link on page 68 opens Experiments with litmus
a virtual experiment in which pupils move the cursor over a range of substances to find the colour of litmus (red, blue or purple).
This could either be used as a simple exercise in observation and inductive reasoning, or as a reinforcement exercise after pupils had done some initial practical work to see if they could apply their
ideas and predict what would happen in a related situation.
1: Practical: Using red cabbage as an indicator
(AB/AT)
This practical is in two parts: pupils first extract the colour from red
cabbage leaves by crushing, dissolving and filtering. The solution obtained from this process is then used to test a variety of household chemicals. The experiment could be introduced as an exercise in deductive reasoning demonstrate the effect of the cabbage juice with a named acid (e.g. hydrochloric) and then ask pupils to use the indicator to classify the substances being tested. Alternatively, you can use this task in an inductive way, with pupils first looking for colour changes. Once the results are summarised, the acids can be defined as that group of substances which turns
the indicator red. Worksheet 7Ec(3) gives all the practical instructions.
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In the red7Ec
3: The litmus test
Pupils are asked to evaluate a number of conclusions based on observations from indicator tests with litmus solution. Although the presence of water as a condition for acidic and alkaline
reactions to be shown is not a required piece of knowledge at KS3,
it is included here as an exercise in logic in a context which will
be simple enough for most pupils to understand. Allocate pupils
one of the conclusions to discuss in groups and report back to the class. After the discussion, pupils could record the findings for all the conclusions. Structured support for recording is provided by Worksheet 7Ec(6).
Homework tasks
1: After checking with an adult, pupils carry out a task at home
similar to Exploring 1 using everyday substances such as fruit juices or cold tea to make indicators. These indicators can then be tested with acids such as vinegar or lemon juice, and alkalis such as toothpaste or soap.
SHOULD
PB pages
6365
Starter 1
Starter 2
Explaining 1
Starter 5
Exploring 3
Plenary 1
Homework 1
Homework 1
Must: Worksheet 7Ec(7) offers highly structured support for
this activity in the planning, carrying out and recording of the work.
Should: Worksheet 7Ec(8) gives structured guidance on the planning, but requires pupils to produce their own written record.
Resources
Worksheets 7Ec(5) and 7Ec(6) (for Must level).
2: Worksheet 7Ec(9) asks pupils to research examples of alkalis
that are used in the home and prepare a poster, leaflet or presentation. Be aware that images downloaded from the internet may be under copyright.
Explaining tasks
1: Pupils Book page 68
This deals with the introductory ideas on indicators and their effect on acids. Worksheet 7Ec(1) is the Access Sheet.
2: Pupils Book page 69 (AT)
This deals with the concept of alkalis, their historical development and gives a simple introduction to their dangers. Worksheet 7Ec(2)
is the Access Sheet.
The second AT presentation link on page 68 opens Acids and
alkalis which provides a list of everyday substances for pupils to classify as acids or alkalis.
Plenaries
1: I can cloze exercise AB/AT
Afl
The second AT document link on page 68 opens a cloze
exercise covering the material on page 68. There is also an AT
presentation version with answers.
2: I can cloze exercise AB/AT
Afl
The AT document link on page 69 opens a cloze exercise
covering the material on page 69. There is also an AT presentation
version with answers.
3: Quick Check
The Quick Check sheet reinforces some of the key words encountered in this topic and also presents an exercise in logic and deduction.
4: Thinking about alkalis (AT)
OOO: butter, milk, soap. (Possible answers: soap is the only one that is made from fats and ashes; milk is the only liquid.)
PMI: no substances should be alkalis. (Possible answers: P we would not get burnt by alkalis; M acids could not be neutralised;
I how would we get rid of the acids in our mouth when we use toothpaste? How would we treat heartburn?)
PMI: only dilute alkalis should be allowed. (Possible answers:
P the hazards of concentrated alkalis would be removed;
M it would be much more expensive to transport alkalis;
I are some alkalis dangerous for reasons other than being alkalis?)
The fourth AT presentation link on page 68 opens Thinking about
alkalis a PowerPoint presentation version of this task.
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Number and title
Level
Location
Type
Tasks
Acids in action
Must/Should
PB p63
Classwork
Explaining 1
Diamonds are for safety
Must
PB p6465
Classwork
Explaining 2
7E
Quick Quiz
Must/Should
ASP
Classwork
Starter 1
7E
Quick Quiz Answer Sheet
Must/Should
ASP
Classwork
Starter 1
7Ea
Quick Check
Must/Should
ASP
Classwork
Plenary 5
7Ea
Word Sheet
Must/Should
ASP
Homework
7Ea(1)
Diamonds are for safety
Must/Should
CHAP
Access
Explaining 2
7Ea(2)
Spot the hazard 1
Must
CHAP
Practical
Exploring 3
7Ea(3)
Spot the hazard 2
Should
CHAP
Practical
Exploring 3
7Ea(4)
Comparing the hazards
Must
CHAP
Classwork
Explaining 3
7Ea(5)
What hazard?
Must/Should
CHAP
Homework
Plenary 2
7Ea(6)
Cracking the Hazchem code 1
Should
CHAP
Homework
Homework 1
7Ea(7)
Cracking the Hazchem code 2
Could
CHAP
Homework
Homework 2
SS12
Thinking Skills
Must/Should
CHAP
Skills Sheet
Exploring 2, Plenary 1
Code
Framework threads
Year 7
Topic
1.1a1
Scientific thinking: developing explanations using ideas and models
Recognise and explain the values of using models and analogies to clarify explanations.
7Ed
1.1a2
Scientific thinking: challenge and collaboration in the development of explanations
Recognise that scientists of all disciplines and nationalities often work together to develop explanations.
7Ed
1.1a3
Scientific thinking: developing argument
Identify a range of scientific data and other evidence to back an argument and the counterclaim in less complex and/or familiar contexts, e.g. establishing a wind farm.
7Ee
Recognise that scientific evidence can be used to support or disprove theories.
7Ee
1.1b
Applications, implications and cultural understanding
Describe some benefits and drawbacks of scientific developments with which they are familiar.
7Ea, 7Eb, 7Ec
Recognise that decisions about the use and application of science and technology are influenced by society and
individuals.
7Ee
Statement
Topic
a
Research, experiment, discuss and develop arguments.
all
b
Pursue an independent enquiry into an aspect of science of personal interest.
7Ea, 7Eb, 7Ed
c
Use real-life examples as a basis for finding out about science.
all
d
Study science in local, national and global contexts and appreciate the connections between these.
7Ea, 7Ee
e
Experience science outside the school environment including in the workplace, where possible.
7Ea, 7Ec, 7Ee
f
Use creativity and innovation in science, and appreciate their importance in enterprise.
7Ea, 7Ee
h
Explore contemporary and historical scientific developments and how they have been communicated.
7Ec, 7Ed
i
Prepare to specialise in a range of science subjects at Key Stage 4 and consider career opportunities that are provided by science qualifications both within science and in other areas.
7Ea
j
Consider how knowledge and understanding of science informs personal and collective decisions, including those on substance
abuse and sexual health.
7Ea, 7Ed, 7Ee
k
Make links between science and other subjects and areas of the curriculum.
7Eb, 7Ee
Statement
Topic
1a
Use a range of scientific methods and techniques to develop and test ideas and explanations.
all
1b
Assess risk and work safely in the laboratory, field and workplace.
all
1c
Plan and carry out practical and investigative activities, both individually and in groups.
all
2a
Obtain, record and analyse data from
a wide range of primary and secondary
sources, including ICT sources, and use their
findings to provide evidence for scientific
explanations.
all
2b
Evaluate scientific evidence and working methods.
7Ec, 7Ed, 7Ee
3a
Use appropriate methods, including ICT,
to communicate scientific information and
contribute to presentations and discussions
about scientific issues.
7Eb, 7Ec, 7Ee
Pupils materials
Statement
Topic
Sc3 2a
To describe changes that occur when materials are mixed.
all
Objectives
All pupils must:
(1) use universal indicator to test solutions for acidity and alkalinity and to measure pH
(2) give examples of everyday substances that are acids and alkalis.
Correctly use the term pH.
Most pupils should:
(3) explain that, in the past, there were a number of competing theories to explain acidity
(4) describe the main features of the pH scale and classify solutions as strong or weak acids or alkalis
(5) identify the pH of a solution using universal indicator.
Correctly use the words strong, weak (as applied to acids and alkalis), universal indicator.
Some pupils could:
(6) explain that all acids contain hydrogen
(7) use ideas about colour mixing to explain how universal indicators are made, and how they work
(8) describe some alternative theories to explain acidity and explain some evidence for the currently accepted theory.
Exemplar topic plans
* This table is repeated in 7Ec.
Topic notes
Targets for the topic can be accessed via the ActiveBook or
ActiveTeach from the link next to the initiator question.
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What is an acid7Ed
Topic task planner
Use these tasks to adapt the exemplar topic plans to your own needs. Many tasks can be adapted to become different types (e.g. starter
rather than exploring). AT or AB/AT at the top of a task means that the task depends on using the ActiveBook and/or ActiveTeach;
where these symbols appear in brackets it indicates that the task can be carried out with or without their use. Also consider using one of the plenaries from the previous topic as a starter task in this topic.
Finding the balance
Must: pupils follow the instructions on Worksheet 7Ed(3) and
record their results on it.
Should: pupils follow the instructions on Worksheet 7Ed(4).
Could: ask pupils to check the values obtained with universal indicator solution against a pH meter. There are a number of small, solid state meters on the market which do not require
extensive and time-consuming calibration, and give a direct read- out of pH to within 0.1.
Eye protection should be worn. No tasting of any chemicals should be allowed.
Starters
1: Mixing indicators
Ask pupils to name three indicators that they used in Topic 7Ec
(e.g. red cabbage, litmus, phenolphthalein, tea, blackcurrant juice) and what colours they turned in different substances. Pupils
could then discuss what they might expect to happen if you mixed two of the different indicators together.
2: Demonstration: Laboratory indicators
Use this demonstration to introduce pupils to the idea that there
are several laboratory indicators. Set up a row of test tubes in pairs, with a different indicator in each pair. Show what happens when
the indictors are mixed together.
Resources (per group)
Dropping pipettes; spotting tiles; a variety of common substances (e.g. vinegar, salt, sugar, lemonade, toothpaste, lemon juice, flour, Milk of Magnesia, bleach, washing powder,
scouring powder); universal indicator solution and colour charts;
pH meter; eye protection; Worksheet 7Ed(3) or 7Ed(4).
Must/should: pour a little strong acid (e.g. dilute HCl) into one of
each pair and note the colour change; repeat with alkali (NaOH).
Could: show the colour in acid and ask pupils to predict the alkaline colour given their understanding of colour mixing (e.g. methyl orange is red in acid, so pupils may be able to predict that the alkaline colour has to be yellow to give the orange colour overall).
Eye protection should be worn. Some indicators may be highly flammable, depending on the solvent.
2: pH testing AT
The first AT video link on page 71 opens Testing pHs a virtual version of the pH experiment in Exploring 1, where pupils can test
a number of substances by rolling the cursor over the picture to get the universal indicator colour.
Resources
Rack with boiling tubes; hydrochloric acid (0.1 mol dm-3) (irritant); sodium hydroxide (0.1 mol dm-3); samples of indicators, e.g. methyl orange, thymol blue.
3: Practical: The dilution challenge
Ask pupils to predict what effect making an acid more dilute would have on pH. The predictions could be investigated or demonstrated. Pupils could also be asked if the acid would become more or less corrosive. Alternatively, set this exercise as a challenge show
pupils that the acid is pH 1, and ask them to find out how much water they would need to add to make it pH 2. In theory, the general rule is that a ten-fold dilution causes a shift in pH by
one unit, but the key learning objective here should be accurate planning, experimentation and data analysis, rather than any specific knowledge outcomes.
Eye protection should be worn.
Exploring tasks
1: Practical: Testing the pH of substances
Ask pupils to test substances using universal indicator solution or paper. Make sure that the colour chart the pupils work from
matches the type of indicator being used paper and solution are significantly different in the range of colours and pH values.
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7EdWhat is an acid?
The AT animation link on page 70 opens pH Testing an
interactive activity that asks pupils to guess the pH of various household substances.
Resources
Hydrochloric acid (0.1 mol dm-3); universal indicator solution; pH
meter (if available); test tubes; measuring cylinders.
2: Pupils Book pages 7273 (AB/AT)
This gives pupils the chance to explore the history of ideas about acids, and the conflict between differing theories and scientists. Worksheet 7Ed(2) is the Access Sheet.
4: Thinking about testing pH (AT)
CAP: a bottle labelled universal indicator has a red liquid inside. (Possible answers: an acid has been added to it; the label has been put on the wrong bottle.)
OOO: stomach acid, skin, blood. (Possible answers: skin is not a liquid; blood is slightly alkaline.)
OOO: red, orange, blue. (Possible answers: blue is the only colour that represents an alkali.)
7Ee
The AT document link on page 72 opens Acid observations a
sequence of statements about acids for pupils to correct.
Plenaries
The first AT presentation link on page 71 opens Thinking about
testing pH a PowerPoint presentation version of this task.
1: Quick Check
Ask pupils to produce questions to fit the answers given on the
Quick Check sheet. Pupils can work in small groups before holding
a short class discussion to decide what the questions should be. This can be done orally or in writing.
5: Practical: Make your own universal indicator
This activity could be suitable as an extension activity for those
who have finished other aspects of the work. Although pupils of all abilities may enjoy the challenge, higher-attaining pupils are more likely to be able to appreciate the necessary logic needed to make a sensible prediction.
2: Thinking about uses of acids and alkalis (AT)
PMI: soaps should be more alkaline. (Possible answers: P they would remove dirt more efficiently; M they would be more damaging to the skin and eyes; I how do soaps react with your skin?)
CAP: what might I need to consider when making a new
shampoo? (Possible answers: the pH; its smell; its cleaning power.)
OOO: 1, 8, 14. (Possible answers: 1 is the only pH number that is an acid; 8 is the only number that represents a weak rather than
a strong acid/alkali.)
The third AT presentation link on page 70 opens Thinking about uses of acids and alkalis a PowerPoint presentation version of this task.
Give pupils bottles of a number of indicators and asked them to
produce a mixture which has the maximum number and/or best
range of colour changes. This problem could be approached simply on a trial and error basis, although it is also possible to predict the effect of a suitable mixture using data tables. There is no practical instruction sheet for this activity, but Worksheet 7Ed(8) covers
linked work as an exercise in deduction for a homework activity.
Eye protection should be worn.
Resources (per group)
Test tubes; dropping pipettes; spotting tiles; set of bottles of different indicators (e.g. litmus, methyl orange, phenolphthalein (highly flammable), thymol blue, bromothymol blue); samples
of solutions at a range of pH values (ideally buffers, but this
is not critical) e.g. hydrochloric acid (pH 1) (corrosive),
ethanoic acid (pH 45) (irritant), water (pH 7) sodium hydrogen carbonate (pH 9), sodium hydroxide (pH 13) (corrosive).
3: I can cloze exercise AB/AT
Afl
The AT document link on page 71 opens a cloze exercise,
covering the content of pages 7071. The third AT presentation link
on page 71 opens a presentation version with answers.
Homework tasks
6: Arguments about acids
This activity illustrates some competing theories in the development of ideas about acids.
Should: this is a comprehension task based on Worksheet
7Ed(5). Pupils extract information from the grid to answer the questions. There are some simple calculations on chronology.
Could: the task involves matching and sequencing. Pupils have to read the text on Worksheet 7Ed(6) very carefully to be able to deduce the clues which allow them to assemble the text boxes in
a logical order.
1: Worksheet 7Ed(7) provides instructions for pupils to make a
pH chart to reinforce some of the ideas introduced during the lesson.
Resources
Scissors; glue; magazine pictures illustrating the different substances. Optional: coloured pencils.
2: Worksheet 7Ed(8) shows pupils, in a simple way, how universal
indicators are made, and takes them through a structured series of questions showing how a suitable mixture of indicators can
give rise to a range of colours.
3: Ask pupils to plan an investigation into the relative merits of different soaps, shower gels, etc. against participant bias (blind testing). This is an opportunity for high-attainers to involve themselves in a planning exercise that could give access to
levels 7 and 8. It also deals with the work of scientists in the world of medical research, and the use of blind testing as a technique for eliminating experimenter bias. Worksheet 7Ed(9) will assist pupils in their thinking.
Resources
Could: Scissors; glue.
Explaining tasks
1: Pupils Book pages 7071
(AB/AT)
This introduces ideas about the pH scale, why it was introduced,
how it gets its name, and how we can use universal indicator to measure pH. Worksheet 7Ed(1) is the Access Sheet.
The second AT video link on page 71 opens Environmental
monitoring discussing how both the external and internal environment of a factory is monitored.
The AT document link on page 70 opens pH which provides captions about pH to be completed.
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What is an acid?
7Ed
In the red
7Ec
Tangy tastes
7Eb
Pupils materials
Acids in action
Objectives
All pupils must:
(1) explain that a neutral solution can be obtained by adding an acid to an alkali
(2) recognise that the building of a chemical factory may cause controversy.
Most pupils should:
(3) describe pH changes on neutralisation or dilution of an acid or an alkali
(4) link the strength of acids and alkalis to the potential hazards
(5) describe some applications of neutralisation reactions
(6) be able to state some arguments for and against the building of chemical factories.
Correctly use the word neutralisation.
Some pupils could:
(7) give a balanced evaluation of the arguments for and against the construction of new chemical facilities.
Exemplar topic plans
Topic notes
Targets for the topic can be accessed via the ActiveBook or
ActiveTeach from the link next to the initiator question.
Be prepared: 7Ee
Exploring 1: racks of tubes may need to be prepared in advance.
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7EeFinding the balance
Topic task planner
Use these tasks to adapt the exemplar topic plans to your own needs. Many tasks can be adapted to become different types (e.g. starter
rather than exploring). AT or AB/AT at the top of a task means that the task depends on using the ActiveBook and/or ActiveTeach;
where these symbols appear in brackets it indicates that the task can be carried out with or without their use. Also consider using one of the plenaries from the previous topic as a starter task in this topic.
7Ea
Starters
Exploring tasks
1: Thinking about acids and alkalis (AT)
1: Practical: Rainbow fizz
This practical reinforces ideas about the pH scale, and also develops pupils ability in observation and following instructions. There is
a real sense of achievement if this experiment works well, but it does need a degree of care. Over-enthusiastic mixing will mean that pupils lose their rainbows. You are advised to check this experiment out first. It is advisable to prepare tubes before the lesson.
Afl
Carry out a Thinking skills exercise to remind pupils of what
they have learned so far about acids and alkalis.
OOO: sulphuric acid, citric acid, ascorbic acid. (Possible answer: sulphuric acid is the only one not present in fruits like lemons and limes.)
OOO: red, blue, yellow. (Possible answers: yellow is not a colour of litmus; blue is the colour of universal indicator with alkalis; the
other two are acid colours.)
OOO: vinegar, sugar, soap. (Possible answers: vinegar is the only acid/liquid; soap is the only alkali.)
OOO: hydrogen, oxygen, sulphur. (Possible answers: hydrogen is the only one thats in every acid; sulphur is the only solid; sulphur
is not in water.)
Must: pupils can record their work using the framework provided
in Worksheet 7Ee(3).
Should: pupils design their own format for recording results.
Make sure that pupils have been shown how to smell chemicals safely. Eye protection should be worn.
Note that there is usually more than one possibility for the odd one
out, and the important outcome is the pupils justification of his/her decision. Give pupils one point for a correct scientific reason, and bonus points if they can think of a reason that no-one else has thought of.
The first AT presentation link on page 76 opens Thinking about acids and alkalis a PowerPoint presentation version of this task.
Resources (per group)
Eye protection; test tube rack; boiling tube containing about
1 g anhydrous sodium carbonate (irritant); tube 1 test tube containing about 2 cm3 water; tube 2 test tube containing
about 10 drops universal indicator; tube 3 test tube containing about 2 cm3 approx. 0.5 mol dm-3 ethanoic acid; tube 4 test
tube containing about 2 cm3 approx. 0.5 mol dm-3 ethanoic acid; Worksheets 7Ee(2) and 7Ee(3).
2: Mixing solutions
Ask pupils to speculate on what the outcome might be if solutions
of given pH values were mixed. You could do this as a brief introductory demonstration, or use it as a discussion exercise.
Pupils may also identify volume as a key variable.
2: Planning a neutralisation investigation
Worksheet 7Ee(5) asks pupils to evaluate critically a number of
plans for a neutralisation investigation. This can be used as a stand- alone activity, or in conjunction with the investigation in Exploring 4.
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Finding the balance7Ee
3: Titration AT
The AT animation link on page 74 opens Neutralise an acid by titration this animation allows pupils to undertake a virtual neutralisation in which they can add an alkali to an acid and watch the change in pH that takes place.
Plenaries
1: Concept map
Ask pupils to draw a concept map linking all the ideas they have encounte