Part 1 – Metals

1. Describe how metals are able to conduct electricity?

2. What is meant by the word “malleable” when referring to a metal?

3. Which property makes metals a good choice for making saucepans?

4. Give 2 reasons for recycling metals.

5. (a) What is alloy? (b) Give an example of an alloy. (c) Why do chemists make alloys?

6. Which box(es) in the grid below contain:

(a) The name of the compound formed when magnesium burns in oxygen? (1 box)
(b) A metal that reacts with cold water? (2 boxes)
(c) A metal that is stored under oil? ( 1 box)
(d) A metal that reacts with acid and not cold water? (2 boxes)
(e) A metal that does not react with acid or water? (1 box)

7. Caesium metal behaves in many ways like potassium and sodium.

(a) Why is caesium stored under oil?
(b) Which gas is released when caesium is added to water?
(c) Name the other product formed in (b)
(d) Write a chemical equation for the reaction in (b)

8. Write word then chemical equations for the following reactions:

(a) Sodium reacting with water (b) Magnesium reacting with hydrochloric acid

(c) Calcium reacting with oxygen (d) Lithium reacting with oxygen

9. List the following metals in order of reactivity: aluminium, copper, gold, iron, lead, magnesium, silver, sodium.

10. A metal with a silvery appearance reacted as follows:
It reacted very slowly with cold water;
It reacted quickly with dilute acid;
It could displace zinc from a solution of zinc chloride.

(a) Name the metal

(b) Write the equation for the metal reacting with hydrochloric acid.

(c) Explain why the metal could displace zinc from zinc chloride.

11. What type of energy change takes place in a battery (cell) when it is producing an electric current?

12. Pick the letter from the box below which shows:

(a) a substance which could be an electrode
(b) a substance which could be an electrolyte
(c) particles that move through wires when electricity is flowing
(d) particles that move through the electrolyte when electricity is flowing

 

13. Explain why silver is a good conductor of electricity yet phosphorus is not.

14. Give an example of a rechargeable battery.

15. A pupil used a piece of zinc, a piece of copper, wires and a beaker of sodium chloride solution to create a cell.

(a) State which direction the current would flow (Zn Cu or Cu Zn)
(b) What is the purpose of the sodium chloride solution?
(c) Which particle flows through the wire when the cell is working?
(d) Suggest a metal which could be used instead of Cu to create a greater voltage.

 

16. The Italian professor, Alessandro Volta, made one of the first batteries. It is called the “Voltaic Pile”.

The diagram opposite shows the pile connected to a meter for measuring current.

(a) When the sodium chloride is replaced with potassium nitrate solution, a reading is obtained on the meter. When the hydrocarbon hexane is used no reading is obtained.
Explain each of these results.

(b) What will happen to the reading on the meter if zinc is replaced by tin?

 

17.

For the cell above:

 

(a) state the direction of electron flow
(b) explain the purpose of the ion bridge
(c) Use page 7 of the data booklet to write ion electron equations for the reactions at the magnesium and tin electrodes.
(d) predict what would happen to the (i) direction of the current (ii) size of the voltage if the magnesium strip was replaced with copper.

18.
(a) What is meant by the terms oxidation and reduction?
(b) In the cell in Q.7, at which electrode is oxidation taking place?

19. When a strip of magnesium is added to a test tube of copper(II) sulphate, the blue colour of the solution disappears and the magnesium strip becomes coated in a brown solid.

(a) What type of reaction is taking place?
(b) What is the brown substance that is seen to form on the magnesium?
(c) Write ion electron equations to show what happens to the magnesium atom and the copper ion.

19. In which of the following reactions will displacement occur?

20. Write ion electron equations for:

(a) the oxidation of aluminium (b) the reduction of zinc(II) ions
(c) the oxidation of sodium (d) the reduction of silver (I) ions
(e) the reduction of lithium ions (f) the oxidation of potassium

21.
(a) Explain what is meant by the term fuel cell.
(b) In what way(s) do fuel cells differ from batteries?