Alun School KS3 Science

Year 8 - Compounds and Mixtures

From KS2, pupils should know:
TSE- 3 a comparison of the features and properties of some natural and man made materials.
TSE-4 the properties of materials relating to their uses
TSE –5 how some materials are formed or produced
All Assessed activities to be completed on paper/graph paper and filed.
Please consult levelling guidance prior to teaching an assessed skill to ensure that pupils access the higher levels for each skill
Please remember to annotate a teacher commentary (on the pupils work) associated with the level you believe they have achieved.
Range – Sustainable Earth 2
The physical and chemical properties of some elements
Assessed tasks (Skills): C3,D1,D4
Lesson 6:  P: Predicting, D: Conclusions and C: Tables – ‘mass of Magnesium Oxide investigation’
Skills covered in unit:

Communication: 2 - communicate logically by speech, writing, drawings, diagrams, charts, tables, bar charts, line graphs, videos and ICT packages using a wide range of scientific vocabulary, terms, symbols and conventions
Communication: 3 – Work quantitatively, using appropriate mathematical conventions and using SI units appropriate to their work.  Eg kg, s, N, m, J, W.
Planning: 4 – when planning a fair test, the key variables that need to be controlled and how to change the independent variable.
Developing: 1 – Use a range of apparatus and equipment safely and with skill, taking action to control the risks to themselves and others.
Developing: 3 – Identify, describe and explain trends, patterns and relationships
Developing: 4 –  use scientific prior knowledge to explain links between cause and effect when concluding
Planning: 1- the choice of success criteria.
Planning: 2 – Predictions using previous knowledge understanding and preliminary work.
Planning: 4 – when carrying out a fair test, control variables appropriately and identify any variables that cannot readily be controlled
Planning: 5 – the number of observations or measurements that need to be made and their range and values to ensure reliability of evidence
Planning: 6 – the equipment and techniques required for the enquiry
Planning: 7 – any potential hazards in their work
Reflecting: 2 - justifying any improvements made to the planned approach/method
Reflecting: 4 – Linking the learning to dissimilar but familiar situations, within and outside school.
Lesson
Range
(Learning outcome)
Teaching & Learning
methodology
Literacy
(inc.
differentiation)
Pupils need to understand the difference between an element and a compound. That elements combine through chemical reactions to form compounds.

Understand that elements join together to make compounds.

Understand that compounds contain atoms of two or more elements.

Understand the term molecule and that this can be used to describe both elements and compounds.
C2 communicate logically using scientific vocabulary and symbols
Scrap paper (A4 cut into 4)




Teacher demo
Burning magnesium in air
Learning Objective:
Be able to explain the difference between a physical and chemical change

Starter
Give each pupil a small piece of (scrap) paper. Ask them to change it physically in some way.
They may do thing like folding it etc.

Then ask them how the paper could be changed chemically.

Write down 3 things that happen in a chemical change (see Spotlight 9, pg132)

Main
Work through page 132. Students could write down the differences between a physical and chemical change (see paragraph at top of pg132).

Answer Q’s a-j (carry out the activity marked by a black ►)

Main2
Pupils need to understand that a compound is made when 2 or more elements join together chemically.
Teacher demonstration – burning magnesium in a gas jar of oxygen

Some stimulus questions that can be used to assess the above skill are - is Mg an elements or compound, why? A metal or non metal? What is it reacting with? What new substance is made? Is it an element or a compound?

Main3

Sheet 8Gc(5) is a good resource for using space filler diagrams- this could be used in a variety of ways.  As a result pupils should understand that some elements exists as atoms and others as molecules.

Sheet 8Gc(6) could be used to develop these ideas, and to differentiate between molecules of elements and compounds. Lego bricks can be used to develop these ideas kinaesthetically.

See also
8Fd pg 86 Exploring Science- compound interest
8Ga The elements of jewellery
These resources can be accessed by clicking on the relevant link in the Exploring Science Activebook

Sheet 8Gc(1) (Optional); good resource for understanding the difference between atoms and elements and compounds

Plenary
8Ga –yr 8 active book- drag and drop activity. This could be used on laptops or on a projector.
Q1 from 8Ga (1)

SPOTLIGHT 7 – Page 28 read and makes notes of information (needed in assessed task). Complete ‘spotting elements and compounds’ and Q1 in yellow box (pg 29).

Skills reflection:  Explaining
L3 – With full assistance pupil is able to explain the difference between an element and a compound.
L4 – With some prompting (very minimal) a pupil can distinguish between an element and compound.  Can remember some compound names.
L5 - No assistance in describing the difference between elements and compounds and name some compounds when given the elements.  With some assistance can show this diagrammatically (or writing word equations).
L6 – No assistance in either describing the differences of elements and compounds or showing this diagrammatically and naming compounds when given the elements.  The pupils can write a word equation for the production of a particular compound.
Homework
Spotlight Sheet 34a (Optional)
Mr Meldrew’s Chemical
Day; Reading for
information


Spelling test
Element
Compound
Atom
Molecule
Magnesium
Aluminium
Oxygen
Iron
Chlorine
Chemical

1+2

3

Fools gold – reaction of iron and sulphur


Use evidence to describe how compounds are different from their elements.

Identify elements and compounds from particle diagrams

D1 – using equipment safely and control risks

C1communication- reading instructions to carry out an enquiry

C2- table


Iron and sulphur


Test 4 should be done as a demonstration

(See page 186 teachers guide)

Learning Objective:

To be able to draw conclusions about the different properties of elements and compounds.


Starter

Recap last lesson by posing the question on the board, “What’s the difference between an element and a compound?”



Main

Use sheets 8Ga(3) students can investigate the difference between iron, sulphur and iron sulphide. Test 4 should be done as a demonstration (See page 186 teachers guide)

Note you  need only to heat a small amount of iron and sulphur in an ignition tube

Pupils can be introduced to word equations here


Plenary

Sheet Ga (2)

Or ask questions based on the L/O

Q1-7 pgs 94/95 exploring science.


Sheet Ga (2)- Literacy



4-5

To begin to be able to write simple formulae for compounds and recognise the elements in a chemical formula.

C2 to communicate using symbols

Exploring Science 8Ga


Exploring Science 8Fd


Spotlight 8


Learning Objective:

 Be able to use symbols to represent chemical compounds.

Be able to write simple formulae for compounds.


Starter

Ask students to draw some simple symbols (with labels) that they already know.  


Main

Spotlight 8 pg 32 can be used to explore how elements are named and the conventions used. Exploring science 8Ga pg 93 Q 3,4,5 can be used to develop ideas on what a chemical formula tells us about the number and type of atoms joined in a compound.


Plenary

Exploring science 8Fd Pg 86 can be used to explore other types of compounds  


Homework

Elements test.

6

Consolidatory lesson to understand how mixtures are different to elements and compounds

C2 to communicate using symbols and diagrams

Learning Objective:

Be able to explain the difference between a mixture and a compound.

Be able to recognise elements, compounds and mixtures from particle diagrams.


Main

8Gc pure dead brilliant

questions in the text are good can also be supported by sheets 8Gc(5) + 8Gc(6) (if not used previously) and 8Gc(7)


Also, students could work through pg32 Spotlight 9.


Plenary

Beg of my neighbour- ask each pupil to write down 3 things they should have learnt and compare notes in pairs.



Skills Reflection

L3 – With full assistance pupil is able to explain the difference between an compound and a mixture.  Cannot identify all three on particle diagrams.

L4 – With some prompting (very minimal) a pupil can distinguish between a mixture and compound.  Can remember some mixture names.  Full assistance required with the particle diagrams.

L5 - No assistance in describing the difference between mixtures and compounds.  Minimal assistance in identifying the differences on particle diagrams.

L6 – No assistance in either describing the differences of mixtures and compounds or showing this in a diagram.

Homework

Spotlight Sheet 27c (Info only)- Two’s Company.  Literacy

7-8

Will magnesium oxide weigh more or less than the magnesium that you started with?


Pupils need to make a prediction according to the above statement and to carry out an investigation to prove their prediction.


Pupils should understand that the mass of MgO is greater than that of Mg and why.

P2 prediction focus of lesson


D2 make sufficient and accurate measurements P(1) success criteria

D1 – using equipment safely

D4- describe patterns

C2- table


Crucible &lid

Pipe clay triangle

Bunsen burner

Heat proof mat

Tongs

Coil of magnesium 2 dec place balance

Note remind pupil to handle the crucible lids carefully and not to break them.

(see tech guide p174 for practical advice).

Exploring Science 8 pg87 HSW


Sheet 8Fd(2) (Info only)



8Fd(3) Optional (literacy) for the more able- they will need to design their own table.


Learning Objective:

 Be able to investigate and explain what happens to the mass of magnesium when it burns.

Be able to make predications about chemical reactions.


Starter

Burn Mg in air in a pair of tongs

Ask the question is Mg an element/metal/non metal?

What is Mg reacting with? What is made? What is the name of the compound?


SKILLS ASSESSMENT:  P: Predicting and D: Conclusions and C: Tables


The following activity assesses the above skills.  Please see the levelling guidance prior to teaching to ensure that all pupils are able to access the higher levels.  


Pupils need to be able to try and predict but also explain their prediction – to access the higher levels pupils must be told to use as much scientific knowledge as possible – you may wish to revisit quickly some previous lessons in this topic to help them.



Please record levels achieved in the ISR.


Main

Will magnesium oxide weigh more or less than the magnesium that you started with?


Pupils need to make a prediction according to the above statement and to carry out an investigation to prove their prediction.


Pupils should understand that the mass of MgO is greater than that of Mg and why.


They could write this up later as the apparatus is cooling. NOTE the experiment needs to start as early as possible in the lesson as time is needed to cool, weigh and draw a conclusion.

This should take place over two lessons


9

The physical and chemical properties of some elements, compounds and mixtures


Production and testing of gases


P3 – finding relevant information

C2 – Pupils can develop communication skills during the   presentation of data.


Text 7Fb p 80-1




7Fb(3)instruction sheets for collection of gases + questions

Learning Objective:

Be able to describe the tests for hydrogen and carbon dioxide


Starter:

Ask pupils how they know if a chemical reaction has taken place – recap signs of chemical reactions from lesson 1

One of the signs is fizzing (gas is produced)

Ask pupils to name some gases they know.


Main idea:  

Some chemical reactions produce gases

How do we tell the difference between these gases?  

We need a range of tests to do this.


Practical or demo

Pupils can use reaction between metal and acid to produce hydrogen gas – lit splint should produce ‘squeaky pop’.  Take care, this may alarm some pupils – best to do this in test-tube rack

What do they think the gas is?



They can then use the reaction between marble and acid (produces carbon dioxide gas) to produce and collect test tubes of ‘another gas’.

They can then test this with a lit splint (should go out) – gas is not hydrogen

Confirm carbon dioxide by adding limewater to tube and shaking – limewater goes milky


Plenary idea:

7Fb1, 7Fb2,  questions on reactions carried out

Project onto whiteboard.


7Fb(6) (Optional)

Which gas is which? – descriptions of some common gases – matching exercise - needs some basic research

+ data for construction of pie chart


10

The physical and chemical properties of some elements, compounds and mixtures


More gas tests

Identification of unknown gases

P1 – choice of success criteria in planning investigation

P6 – equipment and techniques needed in planning conducting investigation.

P7 – potential hazards in planning investigation.


D1 – use range of apparatus safely


C2 – communicate findings


Demo –making and testing for O2, conical, thistle funnel and del tube, stopper bung, water trough, gas jar, beehive , MnO2 and 20vol H2O2, splints and matches




Learning Objective:

Be able to explain  how to test for oxygen

Be able to use gas tests to distinguish between tubes of oxygen, hydrogen and carbon dioxide


Starter:

Ask students what gasses we can test for and how we test for them (recap from last lesson).

Main:

Demo –making and testing for O2, conical, thistle funnel and del tube, stopper bung, water trough, gas jar, beehive , MnO2 and 20vol H2O2, splints and matches


Plenary:

7Fe(6) (Info only) true and false statements – reaction summary includes burning- Literacy


7Fb(4) Fizzy metals 1 or 7Fb(5) (both optional) Fizzy metals 2 for more able (also links to reactivity)

Data sheet linked to gas production



use quick quiz 7F to check understanding so far. Note, This sheet is not provided. Please read through it first and select the questions you want to do. It can be projected.


11

Patterns of behaviour of elements and compounds and their use to describe and predict their behaviour in chemical reactions



Reactivity series of metals

R4 link to dissimilar but familiar situations when considering corrosion of metals.

P6

P7

D2

D4 – use knowledge to explain cause and effect when considering reactivity from previous lessons work.


C2 In making their own reactivity series from lessons practical work.


Learning Objective:  

Be able to understand that some metals are more reactive than others.

Be able to use data from reactions of metals with oxygen, water and acid to make a list of metals in order of reactivity



Starter:  

Why do some metals corrode? Use text 9Fa for pictures of gold, copper and iron for comparison


Main:

Demo reactions of Li, Na, K with water. Students record their observations in their books.


Class prac; students use Mg, Zn, Sn, Fe and Cu in dilute acid (Spotlight

Spotlight 8 page 37) to establish reactivity for these 5


Use combined results to write their own reactivity series


Pupils decide how best to display conclusions in books


9Fd text for data and questions



Plenary:

Discuss results and best way to display them

Questions for thinking:  why is copper used for water pipes when iron is much cheaper?

Why is gold found ‘native’ but magnesium is found as magnesium ore (containing magnesium oxide)?


Q’s 5, 7, 8 on page 75 Exploring Science 9


Skills reflection –

L3 – Full assistance in being able to determine the reactivity series based upon the findings.

L4 – Can make a reactivity series with some assistance but has difficulty in explaining the reasoning behind this.

L5 – Using the findings of the lesson, the pupil is able to with no assistance create the reactivity series with a basic understanding of why (citing evidence from lesson)

L6 – As above but the pupils must show a full understanding of the reactivity of metals giving a full explanation as to why they have been placed where they have.  Pupils at this level are also able to give full and clear answers to questions such as use of metals for things like jewellery, pipes etc.


12

Patterns of behaviour of elements and compounds and their use to describe and predict their behaviour in chemical reactions


Displacement reactions

Carrying out

Observations

C2


P2 – Being able to predict what happens in the displacement reactions.

Learning Objective:

Be able to explain  the concept of displacement  in that a more reactive metal will displace a less reactive one from its compound

Be able to predict the results of displacement reactions


Starter:

Use sheet 9Fb(5) (Optional) to sort metals into order of reactivity with water


Main:

Who would win in a competition between iron and copper?

Demo:

Mix solutions of:

copper sulphate + iron

Iron sulphate + copper


Pupils predict which will react and write their predictions and observations in their books.


Class prac:

Students set up competition reactions between metals and metal compounds. See Spotlight Science 15g


Plenary:

Skills reflection – explaining

L3 – pupil is not able to predict the outcome of a chemical reaction.

L4 – With full assistance, pupil can predict outcomes.

L5 – With minimal prompting a pupil can predict the outcomes of chemical reaction and write word equations to show this.

L6 – As above but the pupil requires no assistance in this task and is able to give a full explanation as to why you can predict the outcome of a chemical reaction.


9Fa quick check sheet (Optional) – word chain - Literacy


Invent metal mnemonic to remember order of reactivity of metals


9Fd(8) + (9) (both optional) metal reactivity in action, matching fact with reason - Literacy


Wordsearch activity sheets – differentiated

9Fd(11) or 9Fd(12) (Optional)

End of Unit Test

ISR and Folder Update

13