Chemistry in Society
Metals
NAT 5
Ink Exercise One
1. Draw the structure of a metal and use the diagram to explain how metals
conduct electricity.
2. Write ionic equations for the following reactions;
(a) Sodium metal being added to water.
(b) Tin metal being heated in oxygen.
(c) Magnesium metal being added to a solution of copper(ii) sulphate.
3. Metals can be obtained from their ores by techniques dependent on their
position in the electrochemical series. State what techniques are used to
extract the following metals from their ores.
(a) Iron from iron(ii) oxide
(b) Aluminium from aluminium oxide
(c) Silver from silver(i) oxide
4. Solid barium sulphate can be produced during the following precipitation
reaction;
barium hydroxide + sulfuric acid → barium sulphate + water
Draw an experimental method that can be used to separate the insoluble barium
sulphate from the reaction mixture.
5. Design an experimental method that can be used to determine the relative
reactivity of magnesium, zinc and tin.
Draw a table of your expected experimental results and use these results to
place the metals in order of reactivity (most reactive first).
6. Define the following terms;
(a) Oxidation.
(b) Reduction.
(c) REDOX reaction.
(d) Spectator ion.
7. The equation for the reaction between magnesium and copper nitrate is:
Mg(s) + Cu2+(aq) + 2NO3-(aq) → Mg2+(aq) + 2NO3-(aq) + Cu(s)
(a)(i) Magnesium atoms are converted into magnesium ions.
Write the ion-electron equation for this process.
(ii) This ion-electron equation is an example of.
(b)(i) Copper ions atoms are converted into copper atoms.
Write the ion-electron equation for this process.
(ii) This ion-electron equation is an example of.
(c)Use the two ion-electron equations (from (a)(i) and (b)(i)) to complete the
REDOX equation for this reaction.
(d)Write down the spectator ion involved in this reaction.
8. The electrolysis of copper(ii) chloride solutions results in the formation of
copper metal at the negative electrode and chlorine gas at the positive
electrode.
(a) Draw an experimental set up that demonstrates the electrolysis of copper(ii)
chloride solution.
(b) Why is a DC supply used in the electrolysis of the copper(ii) chloride solution?
(c) Write ion-electron equations for the formation of;
(i)
Copper metal
(ii)
Chlorine gas
9. Iron can be extracted from haematite (Fe2O3) by heating with carbon monoxide.
Carbon dioxide is also produced. The balanced equation for this reaction is;
Fe2O3
+
3CO
→
2Fe
+
3CO2
(a) Use this equation to identify the reducing agent.
(b) Write the ion-electron equation for the reduction of iron ions into iron atoms.
(c) Calculate the percentage by mass of iron in haematite.
10. Scientists have made cells to produce electricity by connecting todifferent
half-cells together in a circuit.
Half-cells have the metal electrode dipped in a solution of their own ions.
The half-cells have a salt bridge (ion bridge) connecting them.
To complete the cell and record a voltage two connecting wires and a voltmeter
are required.
(a) Draw an experimental set up that demonstrates how a cell can produce
electricity using to half-cells.
(b) State clearly the purpose of the salt bridge.