Uddingston Grammar School
National 5 Chemistry
Metals and Alloys
Unit 3 sub-unit a. Homework 1
1. Which of the following diagrams could be used to represent the structure of
a metal?
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2. In the cell shown, electrons flow through
A.
B.
C.
D.
The
The
The
The
solution from tin to zinc
solution from zinc to tin
connecting wire from tin to zinc
connecting wire from zinc to tin.
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3. Cu2+ + 2e-  Cu
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This ion electron equation represents the
A.
B.
C.
D.
Reduction of copper(II) ions
Reduction of copper(I) ions
Oxidation of copper(II) ions
Oxidation of copper(I) ions
4. Which pair of metals, when connected in a cell, would give the highest
voltage and a flow of electrons from X to Y?
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You may wish to use the data booklet to help you.
A
B
C
D
Metal X
Magnesium
Copper
Zinc
Tin
Metal Y
Copper
Magnesium
Tin
Zinc
5. Which of the following metals would react with zinc chloride solution?
You may wish to use the data booklet to help you.
A.
B.
C.
D.
Copper
Gold
Iron
Magnesium
6. Metallic bonding is a force of attraction between
A.
B.
C.
D.
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Negative ions and positive ions
A shared pair of electrons and two nuclei
Positive ions and delocalised electrons
Negative ions and delocalised electrons.
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7. Four cells were made by joining copper, iron, magnesium and zinc to silver.
Which of the following will be the voltage of the cell containing silver joined
to copper? You may wish to use the data booklet to help you.
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A.
B.
C.
D.
0.5
0.9
1.1
2.7
V
V
V
V
8. In which of the following test tubes will a reaction occur?
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9. The ion-electron equations for the oxidation and reduction steps in the
reaction between sulphite ions and iron(III) ions are given below.
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Oxidation
H2O(l) + SO32-(aq)  SO42-(aq) + 2H+(aq) + 2e-
Reduction
Fe3+(aq) + e-  Fe2+(aq)
The redox equation for the overall reaction is
A.
B.
C.
D.
H2O(l)
H2O(l)
SO42-(aq)
SO42-(aq)
+ SO32-(aq) + Fe3+(aq)  SO42-(aq) + 2H+(aq) + Fe2+(aq) + e+ SO32-(aq) + 2Fe3+(aq)  SO42-(aq) + 2H+(aq) + 2Fe2+(aq)
+ 2H+(aq) + Fe2+(aq) + e-  H2O(l) + SO32-(aq) + Fe3+(aq)
+ 2H+(aq) + 2Fe2+(aq)  H2O(l) + SO32-(aq) + 2Fe3+(aq)
10. Silver jewellery tarnishes in air. This is due to the formation of silver (I)
sulphide. The silver (I) sulphide can be converted back to silver using the
following apparatus.
The equation for the reaction that takes place in the beaker is shown.
3Ag2S(aq)
+
2Al(s) 
6Ag(s)
+
Al2S3(aq)
Calculate the mass, in grams, of silver produced when 0.135g of aluminium
is used up.
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11. Below is a call that contains both a metal and a non-metal electrode.
The ion-electron equation for the reaction taking place at the carbon
electrode is:
I2(aq)
+
2e-

2I-(aq)
a) State the path and direction of electron flow.
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b) What term can be used to describe the reaction taking place at the carbon
electrode?
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12. Iron displaces silver (I) nitrate solution.
The equation for the reaction is:
Fe(s) + 2Ag+(aq) + 2NO3-(aq)  Fe2+(aq) + 2Ag(s) + 2NO3-(aq)
a) This reaction can be carried out in a cell.
A
B
C
State what the three labels, A, B and C should be
b) What is the purpose of the ion bridge?
2PS
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13. Chlorine can be produced commercially from concentrated sodium chloride
solution in a membrane cell. Only sodium ions can pass through the
membrane. These ions move in the direction shown in the diagram.
a) Write the ion-electron equation for the change taking place at the positive
electrode.
You may wish to use the data booklet to help you.
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b) Name solution X.
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14. Bauxite contains impurities such as silicon dioxide.
Silicon can be extracted from silicon dioxide as shown.
SiO2 + 2Mg  Si + 2MgO
Identify the reducing agent in this reaction.
20 Marks
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