Name: Class:

Duncanrig Secondary SchoolEast Kilbride

S2/3 Chemistry Elective Making Electricity

Pupil Booklet Learning Outcomes Homework Summary

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SCN 4-19b Having carried out a range of experiments using different chemicals, I can place metals in an order of reactivity, and relate my findings to their everyday uses.

SCN 3 – 10a I can help to design simple chemical cells and use them to investigate the factors which affect the voltage produced.

SCN 4- 10a Using experimental evidence, I can place metals in an electrochemical series and can use this information to make predictions about their use in chemical cells.

SCN 4 – 10a Using a variety of sources, I have explored the latest developments in chemical cells technology and can evaluate their impact on society.

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Content Statements Can you do this?

1.State that some metals are more reactive than others. 2. Put metals in order of reactivity. 3. State that a cell is apparatus which produces electricity from a chemical reaction.

4. State that a battery is two or more cells joined together. 5. State that electricity passing along metal wires is a flow of electrons.

6. Explain the need to replace batteries in terms of the chemicals being used up in the reaction.

7. Know the difference between a dry and wet cell. 8. State that some batteries are rechargeable, e.g. car battery - lead-acid battery.

9. State that during the charging of a cell electrical energy is changed into chemical energy and the opposite during discharging.

10. State that electricity can be produced by connecting different metals together (with an electrolyte) to form a cell.

11. Explain the purpose of the electrolyte is to complete the circuit.

12. State that electrons flow from one metal to the other and this current can be detected by an ammeter.

13. State that voltage is the force which the cell produces to push the electrons around the circuit.

14. State that voltage can be measured using a voltmeter.

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15. State that the voltage between different pairs of metals varies and that leads to the Electrochemical series.

16. State that electrons flow from the metal higher to the metal lower in the Electrochemical series.

17. State the further apart the metals are in the Electrochemical Series the higher the voltage.

18. State that electricity can be produced in a cell by connecting two different metals in solutions of their metal ions.

19. State the purpose of the “ion bridge” is to complete the circuit by allowing the ions to move.

20. Using the electrochemical series, predict the flow of electrons when two metals are joined in a cell.

21 State that electricity can be produced in a cell when at least one of the half-cells does not involve metal atoms.

22. Research modern developments in fuel cells.

CommentsWhat I need to learn for the Making Electricity test:......

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Homework 1 –

1. What is the meaning of the term electricity?

2. What is a cell?

3. What is a battery?

4. How does a battery produce electricity. ?

5. What energy changes take place when a battery is in use?

6. Give an advantage and disadvantage of a battery compared to mains electricity.

7. Explain why a battery becomes run down.

8.Some batteries are rechargeable. What does this mean?

9. What energy changes take place when a battery is recharging?

10.Give an example of a rechargeable battery.

11. What is the acid used in a car battery?

12. Explain why some cells can be called a dry cell.

Homework 1 – Answers

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Homework 2

1. A chemical cell can be set up and an electric current produced. What do we use to measure the electric current.?

2. A voltmeter is used to measure voltage. Explain the term voltage.

3. What is the meaning of an electrolyte?

4. What is the electrolyte in the fruit cell shown below?

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5. What is the Electrochemical Series?

6. Place the following metals in order of how easily they lose electrons;-

Copper, magnesium, sodium, silver, calcium, iron, lead, potassium

7.

(a) What is the purpose of the salt bridge?

(b) In which direction will the electrons flow in the above circuit?

(c) Name a metal that could be used in place of the magnesium to produce a higher voltage.

(d) What happens to the mass of the magnesium ribbon if the circuit is left running for a few days?

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(e) Cu2+ (aq) ions are blue. What will happen to the blue colour in the beaker containing the copper Cu2+(qa) ions if the cell is left running for a few days.?

Homework 2 – Answers

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Summary - Making Electricity

Fill in the missing words by choosing the correct word from the box. Words can be used more then once.

paste electrolyte copper electrons electrochemicalchemical unreactive metals charging complete

recharged reactive wet higher electricity

current larger ions external different

battery atoms cell efficient voltmeter

The reactions of 1_____________ with oxygen, water and acid can be used to establish an order of reactivity.

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Potassium (most reactive)SodiumCalciumMagnesiumZincCopper (least reactive)

Batteries provide us with a convenient and portable source of 2__________________.

All batteries contain chemicals.

3_______________energy Electrical energy

The electrical energy formed is a flow of 4________________ which passes through metal wires.

Apparatus used to make electricity is called a 5___________.A 6_______________ is two or more cells joined together.

7_________ cells eg. car batteries – lead/acid battery – contain a liquid substance.Dry cell eg. torch battery – zinc/carbon cell – ammonium chloride 8______________.

All cells eventually run down. This is because the chemicals inside have been used up.Some batteries eg. mobile phone batteries - can be 9____________________.

10_________ Electrical energy Chemical energy

Discharging Chemical energy Electrical energy

Electricity can be made by connecting different types of metal together with an 11_______________ eg. salt solution. The purpose of the electrolyte is to 12_____________ the circuit.

Electrons flow from the zinc metal to the copper metal through the 13______________ wires.

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Zinc atoms lose electrons and change to zinc ions.

Zn(s) Zn2+(aq) + 2e-

The 14______________ flowing in a circuit can be measure using an ammeter.

The voltage of a cell can be measured using a 15______________. The voltage is the force that the cell produces to push the 16____________ around the circuit.

Different pairs of metals connected in a cell produce different voltages. This leads to the 18____________________ series which lists metals in order of their reactivity. The higher the metal in the electrochemical series the more 19_________________ it is. Reactive metals lose electrons more easily than 20_________________ metals.

In a cell:

Electrons flow from the metal 21____________ in the Electrochemical series to the metal lower. Metals which are far apart in the Electrochemical series produce 22___________ voltages than metals which are close together.

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Fruit cell - A simple cell can be made by sticking two 17______________ types of metals into a citrus fruit eg lemon and connecting with wires

Electricity can also be made by connecting two different metals in solutions of their metal ions with a salt/ion bridge used to 23_______________ the circuit.

Electrons flow from the more reactive zinc metal to the less reactive copper metal.

Zinc atoms lose electrons to form zinc 24___________

Zn(s) Zn2+(aq) + 2e-

The electrons flow through the external wires and the voltmeter. The electrons are taken up by the copper ions in solution and form 25____________.

Cu2+ (aq) + 2e- Cu(s)

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It is possible to produce electricity by joining a metal half cell with a non-metal half-cell.

Ion-electron equations:

Ni(s) Ni2+(aq) + 2e-

I2(aq) + 2e- 2I-(aq)

Modern developments in cell technology have led to the production of more 26___________________ fuel cells.

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