AQA GCSE Chemistry Teacher Guide

180 Pages·2017·5.17 MB·English

AQA
GCSE
9–1
Chemistry
Teacher Support
Guide
Owen Mansfi eld
References to the textbooks in this teacher resource guide
References to the student textbooks for figures or tables are given in the following style:
■ The first figure or page number always refers to the GCSE Chemistry book.
■ The numbers in brackets refer to the Combined Science Trilogy books.
■ Where there are two numbers in brackets, the first is for Combined Science Trilogy 1 or 2; the second
number
refers to the all-in-one Combined Science Trilogy book.
Use Figure 14.6 (21.4) from page 181 (31; 387) to show …
The figure number The figure number The page The page number The page
in the GCSE in the Combined number in the in the Combined number in the
Chemistry book Science Trilogy GCSE Chemistry Science Trilogy 2 Combined
books book book Science Trilogy
all-in-one book
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© Owen Mansfield 2018
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A catalogue record for this title is available from the British Library
ISBN 978 1471 851186
Contents
1 Atomic structure and the periodic table 1 4 Chemical changes 60
Subatomic particles 1 The reactivity series of metals 61
Atoms and elements 2 Displacement reactions 61
Compounds 3 Oxidation and reduction 62
Relative atomic mass and electron configuration 3 Extraction of metals by reduction 63
A model of the atom 4 pH scale 64
The periodic table 5 Neutralisation 64
Group 0 and introduction to Group 1 6 Strong and weak acids 65
Reactions of Group 1 7 Reactions of acids and metals 66
Introduction to Group 7 7 Neutralisation reactions 67
Reactions of the halogens 8 Salt production 67
The transition metals 9 Making soluble salts 68
The history of the periodic table 9 Introduction to electrolysis 69
Mixtures compared to compounds 10 Electrolysis of molten ionic compounds 70
Separating mixtures 11 Using electrolysis to extract metals 70
Answers 11 Electrolysis of aqueous solutions 72
Using half-equations 73
2 Bonding, structure and the properties of
Answers 73
matter 21
5 Energy changes 83
Ionic bonding 22
Ionic compounds 22 Energy changes in reactions 83
Properties of ionic compounds 23 Investigating energy changes 84
Properties of small molecules 24 Energy profiles 85
Covalent bonding 25 Bond energies 85
Polymers 25 Calculating energy changes 86
Giant covalent structures 26 Cells and batteries (Chemistry only) 87
Metallic bonding 27 Fuel cells 87
Properties of metals and alloys 27 Answers 88
Review of bonding and structure 28
6 The rate and extent of chemical change 94
Explaining states of matter 29
Nanoscience 29 Rate of reaction 94
Review of giant covalent structures 30 Graphs and gradients 95
Different forms of carbon 31 Factors affecting chemical change 96
Answers 31 Colour change or turbidity 96
Collision theory and concentration 97
3 Quantitative chemistry 42
Investigating effect of temperature 98
Relative mass and moles 43 Investigating surface area 98
Using the mole 43 Catalysts 99
Conservation of mass 44 Reversible reactions 100
Balancing chemical equations 45 Equilibrium 100
Mass changes with gases 45 Changes in concentration 101
Reacting masses 46 Changes in temperature 102
Using moles to balance equations 47 Answers 103
Limiting reactant 47
7 Organic chemistry 110
Percentage yield (Chemistry only) 48
Atom economy (Chemistry only) 48 Crude oil and hydrocarbons 110
Gas volumes (Chemistry only) 49 Alkanes 111
Concentration of solutions 50 Fractional distillation of crude oil 112
Concentration and moles (Chemistry only) 50 Properties of hydrocarbons 113
Titrations (Chemistry only) 51 Cracking and alkenes 114
Answers 52 Alkenes (Chemistry only) 114
Reactions of alkenes (Chemistry only) 115 Greenhouse gases and human activity 146

Representing reactions of alkenes (Chemistry only) 116 Evaluating evidence on climate change 146
Alcohols (Chemistry only) 116 Global climate change 147
Reactions of alcohols (Chemistry only) 117 Products of combustion 148
Carboxylic acids (Chemistry only) 118 Pollutants from fuels 148
Reactions of carboxylic acids (Chemistry only) 119 Effects of atmospheric pollution 149
Addition polymerisation (Chemistry only) 119 Answers 149
Condensation polymerisation (Chemistry only) 120
10 Using the Earth’s resources 156
Natural polymers 121
DNA (Chemistry only) 122 Using the Earth’s resources 156
Answers 122 Reducing the use of resources 157
Life cycle assessments 158
8 Chemical analysis 130
Potable water 158
Pure substances and formulations 131 Analysis and purification of water samples 159
Chromatography 131 Waste water treatment 159
Tests for hydrogen and oxygen 132 Corrosion 160
Tests for carbon dioxide and chlorine 133 Preventing corrosion (Chemistry only) 161
Flame tests (Chemistry only) 134 Alloys as useful materials (Chemistry only) 162
Metal hydroxide tests (Chemistry only) 135 Alternative methods of extracting metals 162
Tests for carbonates, halides and sulfate Ceramics, composites and polymers (Chemistry only) 163
(Chemistry only) 135 Useful materials (Chemistry only) 164
Using chemical tests (Chemistry only) 136 The Haber process (Chemistry only) 164
Instrumental methods (Chemistry only) 137 Dynamic equilibrium and the Haber process
Flame emission spectroscopy (Chemistry only) 137 (Chemistry only) 165
Answers 138 Production of NPK fertilisers (Chemistry only) 166
Use of NPK fertilisers (Chemistry only) 167
9 Chemistry of the atmosphere 144
Answers 168
Development of the Earth’s atmosphere 144
How the atmosphere changed 145
iv
1 Atomic structure and the periodic table
1 Atomic structure and the ● Each element has its own type of atom, which
has different properties to the atoms of other
periodic table
elements.
● Elements are either metals or non-metals, and
Overview the properties of metals are different to those of
Specification points non-metals.
4.1.1.1 Atoms, elements and compounds; 4.1.1.2 ● Elements contain only one type of atom, while
Mixtures; 4.1.1.3 The development of the model compounds contain two or more different types
of the atom; 4.1.1.4 Relative electrical charges of atoms chemically bonded together.
of subatomic particles; 4.1.1.5 Size and mass ● A chemical formula shows the relative
of atoms; 4.1.1.6 Relative atomic mass; 4.1.1.7 proportions of each type of atom present in a
Electronic structure; 4.1.2.1 The periodic table; substance, e.g. H O.
2
4.1.2.2 Development of the periodic table; 4.1.2.3 ● The periodic table shows all the elements
Metals and non-metals; 4.1.2.4 Group 0; 4.1.2.5 listed in rows and columns. The rows are called
Group 1; 4.1.2.6 Group 7; 4.1.3.1 Transition metals Periods, and the columns are called Groups.
comparison with Group 1 elements; 4.1.3.2 Typical ● Substances can be pure, containing only one
properties of transition metals type of element or compound, or impure,
containing a mixture of elements or compounds.
Textbook chapter references
AQA GCSE (9–1) Chemistry: Chapter 1 pages 1–31 Common misconceptions
Many students have a few misconceptions associated
AQA GCSE (9–1) Combined Science Trilogy 1:
with this chapter, as a lot of the material is
Chapter 9 pages 116–146
relatively new to many learners. Calculations of
AQA GCSE (9–1) Combined Science Trilogy: relative atomic mass (A) may trouble students who
r
Chapter 9 pages 116–146 are less-confident mathematicians, particularly if
they do not use brackets appropriately, so be ready
Recommended number of lessons: 14
for these possible issues.
Chapter overview Preparation
Contains AQA required practical No The T&L Prior knowledge catch-up teacher sheet
reviews KS3 prior learning and gives advice on
Contains higher-only material Yes
how to begin this topic. The T&L Prior knowledge
Contains chemistry-only material Yes
catch-up student sheet gives a good review of what
Useful Teaching and Learning resources students may recall from KS3, and has questions
to check their understanding of this content. The
• Learning outcomes
T&L Topic overview provides a useful review of the
• Prior knowledge catch-up student sheet
entire topic and would make a useful resource when
• Prior knowledge catch-up teacher sheet
revising the chapter prior to the end of chapter test.
• Topic overview
• Lesson starter 1
Subatomic particles: Lesson 1
• Lesson starter 2
• Lesson starter 3
• Key terms Learning outcomes
• Homework task (a)
• Homework task (b) 1 Relate size and scale of atoms to other
• Quick quiz 1 objects.
• Quick quiz 2 2 Draw the general structure of an atom.
3 Define the relative charge and mass of
• Quick quiz 3
subatomic particles.
• Quick quiz 4
4 Calculate numbers of protons, neutrons and
• Answers to homework tasks
electrons when given the atomic number and
• Answers to all questions mass number.
• Diagram bank
Useful prior learning Suggested lesson plan
● All matter is made up of particles, and these Starter
particles may be atoms, groups of atoms called Start the lesson by asking students what they
molecules, or ions. know about atoms (there is often a wide range
1
e of prior knowledge about atoms at this stage), Atoms and elements: Lesson 2
bl
including how big they think atoms are, and
a
t whether atoms have a structure or not. The T&L
c Learning outcomes
di Lesson starter 1 could be used as an effective
o
ri analogy to get across the relative sizes of the
pe atom and nucleus, and the fact that atoms are 1 Define atoms as the smallest part of an
e mostly empty space! element.
h 2 Describe the format of the periodic table and
t
d Main find given elements in terms of group and
n
a Review the nuclear model of atoms using period.

e Figure 1.1 (9.1) on page 3 (118) of the textbook 3 Define names/symbols of first 20 elements,
r
tu (also available in the T&L Diagram bank) and Group 1 and Group 7.
c
u then introduce the three subatomic particles,
r
t their relative charges, relative masses and
s Suggested lesson plan
c location in an atom. Then introduce atomic
mi Starter
numbers and mass numbers as the number of
o Begin the lesson by asking students to complete
t protons, and number of protons and neutrons in
A the ‘Show you can’ table on page 5 (120) of the
1 an atom respectively.
textbook. Alternatively, you could review the
Show students a periodic table that clearly shows answers to the ‘Test yourself’ from page 3 (118)
these two numbers for each element. Take time to of the textbook (if these were set for homework
emphasise the size of atoms and the meaning of during Lesson 1).
nanometres, and the reason why atoms have no
Main
overall charge.
Give students a copy of the periodic table (a
Plenary completed version is available in the T&L Diagram
Using copies of the periodic table, ask students bank) and annotate appropriately to show group
to deduce the number of protons, neutrons and (column) numbers and period (row) numbers. Ask
electrons in the atoms of a range of elements using students to identify a range of elements from their
just the atomic number and mass numbers for position (group number and period number) in the
those elements. Try to avoid elements like chlorine periodic table.
and copper at this stage as they have mass
Ask students to describe how the elements are
numbers that are not whole numbers.
arranged in the periodic table, and link this to
Support increasing atomic number. At this stage it might
Those students with a weak grasp of the KS3 be a good idea to introduce the idea that although
prior learning should complete the T&L Prior elements are arranged in order of atomic number,
knowledge catch-up student sheet. Some they are also arranged in terms of their chemical
students will need support working out that properties, with elements in the same group all
the number of neutrons can be calculated by having similar chemical properties. Demonstrating
subtracting the atomic number from the mass the reactivity of two or three alkali metals with
number of an element. water would emphasise this point nicely.
Extension Plenary
Some students may ask how chlorine and Ask students to give you as much information as
copper can have mass numbers of 35.5 and 63.5 they can, based on what they have learnt so far,
respectively. These students could be asked to for the element selenium (Se). This should include
find out about isotopes and relative atomic the number of each type of subatomic particle,
masses. the fact that it is a non-metal, and its group and
period numbers.
Homework
Students could complete the ‘Test yourself’ Support
questions on page 3 (118) of the textbook, which Some students may need reminding of how to
focus on the size of atoms, and representing these calculate the number of neutrons using atomic and
sizes using standard form. mass numbers.
2
1 Atomic structure and the periodic table
Extension Plenary
Students could be asked to research the most Give students two or three simple symbol
recent discovery of a new chemical element, and equations, and ask them to construct word
how that element was created/discovered. equations for them by determining the names of
the reactants and products. For instance:
Homework
4Al + 3O → 2Al O would give the word equation:
Students could be asked to learn the chemical 2 2 3
aluminium + oxygen → aluminium oxide. Students
symbols for the first 20 elements for a quick quiz
can ignore the balancing numbers at this stage.
next lesson.
Support
Some students will need support in understanding
Learning outcomes
which elements the numbers in a chemical formula
refer to. For instance, in Na CO , the subscript ‘2’
2 3
1 State that compounds are formed from refers to the number of sodium (Na) atoms only,
elements by chemical reactions. and the subscript ‘3’ is for the oxygen atoms only.
2 Name compounds from given formula or The absence of a number beside a chemical symbol
symbol equations. means just one of those atoms in present (so there
3 State the proportions of each atom in a is just one C atom). Opportunities to practice this
chemical formula.
skill throughout the year should not be missed for
less-confident learners.
Compounds: Lesson 3 Extension
More-confident learners could be shown formulae
Suggested lesson plan
that include brackets and asked to determine the
Starter
total number of atoms in each formula. For instance
Either complete a quick quiz on the symbols for
Zn(OH) , Pb(NO ) , (NH ) PO or Al (SO ) .
the first 20 elements (if this was set for homework 2 3 2 4 3 4 2 4 3
in the previous lesson), or begin the lesson by Homework
showing students a variety of chemical formulae Confidence in determining the number of atoms
and asking them to identify the elements present in a formula is vital for balancing equations later
in these formulae. in this course, so students need as much practice
as possible. Give students another list of chemical
Main
formulae and ask them to deduce the numbers of
Review what students understand by the term
each type of atom present.
‘compound’ and define ‘compounds’ appropriately. Link
the idea that compounds contain elements chemically
Relative atomic mass and electron
bonded in fixed proportions to their chemical formula.
configuration: Lesson 4
For instance, water always has two hydrogen atoms for
every oxygen atom, hence the formula H O.
2
Give students a list of simple, common chemical Learning outcomes
formulae and ask them to name as many of them as
they can from the elements present in the formulae.
1 Define the term isotope.
For instance: NaCl is sodium chloride, CO is carbon
2 2 Define and calculate relative atomic mass.
dioxide. Other suitable formulae could be: K O
2 3 Represent electron configuration by diagram
(potassium oxide), HCl (hydrochloric acid), MgF or by numbers.
2
(magnesium fluoride), Al O (aluminium oxide), LiBr 4 Define the term ion and deduce charge when
2 3
electrons are gained or lost.
(lithium bromide), CaCl (calcium chloride), Cu O
2 2
(copper(I) oxide), Cs S (caesium sulfide), Mg N
2 3 2
(magnesium nitride) and NaOH (sodium hydroxide). Suggested lesson plan
Starter
If necessary, review the rules for the naming
Begin the lesson by revising how to determine the
of simple compounds. Using the same list of
numbers of each type of subatomic particle in an
formulae, ask students to calculate the number of
atom from the atomic and mass number; 31P could
each type of atom present in the formula, and the
be used.
total number of atoms present.
3
e Main Support
bl
This is a busy lesson, and may need more than Some students seem not to understand the
a
t 1 hour to complete. Introduce the idea of isotopes word ‘abundance’. Check this as you work
c
di as atoms of the same element (so with the same through isotopes. Many students will not be
o
ri atomic number) but with different numbers of confident of how to use the brackets on their
e
p neutrons (so different mass numbers). The three scientific calculators properly to complete the A
e isotopes of hydrogen: hydrogen (1H), deuterium, calculations. Going through one or two of these r
h
t (2H or 2D), and tritium (3H or 3T) are useful calculations, showing where to place brackets, will

d
n examples, and Table 1.2 (9.2) on page 4 (120) be necessary. For instance: to calculate the A of
a r
of the textbook shows the common isotopes Cl, the calculation is [(35 × 75) + (37 × 25)]/100
e
ur of carbon. Students could quickly determine = 35.5.
t
c the number of neutrons in the following sulfur
u Extension
r isotopes: 32S, 33S and 36S. Stress that the chemical
st More-able mathematicians may be able to calculate
properties of isotopes are the same because they
c the relative abundances of isotopes from the
mi have the same number of electrons.
A of an element and the mass numbers of its
o r
t Then introduce the concept of relative atomic mass isotopes. For instance, boron has an A of 10.8,
A
r
1 (A): the weighted mean mass of the atoms of and two common isotopes, 10B and 11B. From this
r
an element, or the average mass of the atoms of information it is possible to calculate that 10B has
an element that takes into account the different an abundance of 19.9% and 11B is 80.1%.
masses and relative abundance of the different
Homework
isotopes of an element. Show students how to
The questions in ‘Test yourself’ on page 5 (120)
calculate the relative atomic mass from isotope
of the textbook review the isotopes and A
mass numbers and their abundances (chlorine is r
calculations nicely. Also the T&L Quick quiz 1 also
a good example to use), and then give plenty of
reviews atomic structure and ions, as does the T&L
opportunities for them to practise this type of
Homework task (a) activity. Question 4 of the
calculation. The questions in ‘Test yourself’ on
Chapter review questions on page 26 (141) of the
page 5 (120) of the textbook are suitable, or use
textbook looks at isotopes and ions.
the following isotope data (answers in brackets):
● Cu: 63Cu = 69.2%, 65Cu = 30.8% (A = 63.6) A model of the atom: Lesson 5
r
● Si: 28Si = 93%, 29Si = 5%, 30Si = 2% (A = 28.1)
r
● S: 32S = 95%, 33S = 0.8%, 34S is 4.2% (A = 32.1) Learning outcomes
r
Given the time restraints in this lesson, these A
r
calculations should probably be set for homework. 1 Describe the plum-pudding model.
2 Describe how alpha particle scattering
Now introduce electronic configurations: how
experiments led to development of nuclear
electrons are arranged in energy levels, or shells,
model.
around the nucleus, giving examples of how we
3 Describe how Niels Bohr adapted the model
can represent this arrangement using diagrams to include the idea of protons.
and numbers (e.g. 2.8.1 for Na). Students may 4 Describe how James Chadwick provided
need to be reminded how to deduce the number evidence for existence of neutrons.
of electrons in any atom. Only complete electronic 5 Evaluate how new experimental evidence
configurations for the first 20 elements as after may lead to a scientific model being changed.
calcium this simple model breaks down.
Plenary Suggested lesson plan
Using Figure 1.10 (9.11) on page 12 (128) of the Starter
textbook (or T&L Lesson starter 2), ask students Review the electronic configurations of sodium,
if they can see a link between the electronic fluorine and magnesium, and then asks students
configuration of the atoms and their position what would happen if we took the outermost
in the periodic table. They may notice that the electron away from the sodium atom. What would
number of electrons in the outer shell is equal happen to the overall charge of the particle? In
to the group number, and the number of shells is this way introduce the concept of ions, and then
equal to the period number. look at what happens when we add an electron to
4
1 Atomic structure and the periodic table
the outermost shell of a fluorine atom. Take care The periodic table: Lesson 6
to explain the overall charge of the ion in terms
of the number of protons (positively charged) Learning outcomes
and electrons (negatively charged). Extend these
ideas to magnesium ions (Mg2+), oxide ions (O2–),
1 Identify metals and non-metals on the
aluminium ions (Al3+) and nitride ions (N3–). The
periodic table.
‘Show you can’ activity on page 7 (122) of the
2 Explain the difference between metals and
textbook reviews atomic structure and ions well.
non-metals.
Main 3 Compare outer-shell electron arrangements
to group numbers and chemical properties.
Access to the internet would be ideal for the rest
4 Explain how atomic structure relates to
of this lesson, or the research task could be set
position in the periodic table.
as a homework task prior to this lesson. Split the
class into groups of six and give each member
of the group one of the following scientists to Suggested lesson plan
research individually: Starter
Display an image of the periodic table (like Figure
● John Dalton (1766–1844) 1.7 (9.8) on page 9 (125) of the textbook – also
● J.J Thomson (key discovery in 1897 and his available in the T&L Diagram bank) and use this
‘Plum pudding’ model in 1903)
as a starting point to review a lot of the learning
● Ernest Rutherford (key discovery in 1911, with to date (atomic numbers and mass numbers, groups
help from Hans Geiger & Ernest Marsden)
and periods of the periodic table, and electronic
● Henry Moseley (key discovery in 1913) configurations). Remind students of the link
● Niels Bohr (key discovery in 1913) between the electronic structure of an element and
● James Chadwick (key discovery in 1932) the position of the element in the periodic table.
Each student should try to find out what each
Main
scientist discovered, and how this discovery
Revise the prior KS3 learning on the properties
changed our scientific model of the atom.
of metals and non-metals. Students could then
10–15 minutes of research should be sufficient.
burn a small piece of magnesium metal and test
Then, working as a group again get the students the product using Universal Indicator, showing
to compile a time line to show how the scientific that it is alkaline. Then demonstrate the burning
model of the atom has changed. of sulfur in oxygen using a gas jar of oxygen
and a deflagrating spoon to hold the sulfur (this
Plenary
must be carried out in a fume cupboard). Add
Review the key discoveries of the six scientists
a few drops of Universal Indicator to the gas
in the list, and how the model of the atom has
jar once the reaction is over to show the acidic
changed over time.
nature of the product. Then review the differences
Support between metals and non-metals; Table 1.7 (9.8)
Many students need support when determining on page 10 (125) of the textbook reviews these
the overall charge on an ion. Take care to check differences nicely.
their understanding of the charges on protons and
Create word equations for the burning of
electrons, and how these charges can cancel out
magnesium in oxygen, and of sulfur in oxygen,
(in atoms) or not (in ions).
and give the formulae of the products (MgO and
Extension SO ). Remind students that these products are
2
More-confident learners could be asked to both compounds, and introduce the idea that
determine the numbers of protons and electrons in MgO is an ionic compound (formed as a metal has
polyatomic ions like NH +, SO 2–, NO – and PO 3–. reacted with a non-metal and electrons have been
4 4 3 4
transferred from the metal atoms to the non-metal
Homework
atoms) while SO is a covalent compound where
It may be necessary for students to complete their 2
electrons are shared between atoms.
timelines for atomic theory for homework. If not,
the ‘Test yourself’ and ‘Show you can’ activities on If you have time, discuss the formation of Mg2+
page 8 (124) review the development of atomic and O2– ions and revise how these ions have gained
theory nicely. their respective charges.
5
e Plenary Main
bl
Show students a list of simple compounds and Watch the helium video clip from the University
a
t ask them to deduce whether the compounds are of Nottingham Chemistry Department Periodic
c
di ionic or covalent. Suitable compounds would Table of videos website (www.periodicvideos.
o
ri include sodium chloride (NaCl), potassium oxide com) and use this to develop the idea that all
e
p (K O), methane (CH ), carbon dioxide (CO ), noble gases are relatively unreactive gases due
2 4 2
e sodium carbonate (Na CO ), sulfuric acid (H SO ), to their electronic configuration. Give students
h 2 3 2 4
t the boiling points of the noble gases (Table 1.9
magnesium nitrate (Mg(NO ) ), aluminium bromide
d
n 3 2 (9.10) on page 13 (129) of the textbook) and ask
a (AlBr ), copper sulfate (CuSO ) and ammonia (NH ).
3 4 3 them to plot them as a graph (let the students
e
ur Support decide what sort of graph they should use; most
t
c Some students will need to be reminded about how will opt for a bar graph, but more-able students
u
r they can tell whether an element is a metal or a could be asked to plot boiling point against
t
s
non-metal in order to determine the nature of a relative atomic mass, and then to draw a line of
c
mi compound. best fit through the data points). Use the graphs
o to describe the trend in boiling points of the
At Extension
noble gases.
1 More-confident learners might be able to explain
the formation of ions during the reaction of a Now ask students to complete the electronic
metal with a non-metal by themselves. They could structures of lithium, sodium and potassium and
be asked to show that when aluminium reacts with ask them what all three electronic configurations
chlorine, the ions formed are Al3+ and Cl–. They have in common. Show students the three metals,
could then be asked to explain why the correct emphasising how soft they are (they can all be
formula for aluminium chloride is AlCl . cut using a scalpel, and get softer going down the
3
group). Add them separately to water to show their
Homework
high reactivity and their low density.
Students could create a table/poster/animation
showing the key differences between metals Plenary
and non-metals in terms of their physical and This is an opportunity to revise the formation of
chemical properties. Question 6 of the Chapter ions. Ask students to suggest what will happen to
review questions (page 27 (142)) reviews the the outermost electron of a Group 1 metal when
types of compounds formed from different types it reacts, and hence determine the charge on any
of elements. Group 1 metal ion. Again, using numbers and
charges of protons and electrons will help to clarify
Group 0 and introduction to Group 1: why the overall charge on any Group 1 ion is M+.
Lesson 7 Support
Graph skills are often highly varied at the start of
Learning outcomes KS4, and it is worth checking the graph drawing
ability of your teaching group in this class. Some
students will need support choosing the correct
1 Explain in terms of outer-shell electrons why
type of graph to draw and when creating suitable
Group 0 are unreactive.
2 Describe the trend in boiling points down scales for their graphs, be sure that their scales are
Group 0. continuous and negative!
3 State that Group 1 are called the alkali metals
Extension
and have a single electron in their outer shell.
More-confident graph plotters should be
4 Describe the softness and density of Group 1
encouraged to plot a scatter graph of relative
metals compared to other metals.
atomic mass on the x-axis and boiling point on the
5 Describe the trend in melting point of Group 1
metals. y-axis. A smooth curve of best fit through the data
points will clearly show the trend in boiling points
down the group.
Suggested lesson plan
Starter Homework
Begin the lesson by asking students to complete Another opportunity to practise graph drawing will
the electronic structures of helium, neon and be beneficial to many students. Using Table 1.11
argon, and ask them what all three electronic (9.13) on page 14 (130) of the text book, students
configurations have in common. can plot a scatter graph of relative atomic mass
6