Units 11 and 12 Revision

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Standard Grade Revision
Units 11 and 12
Q1. The box contains the names of some metals.
You may wish to use page 8 of the data booklet.
magnesium
lithium
calcium
nickel
aluminium
potassium
(a) Identify the metal which was discovered in 1827.
(b) Identify the transition metal.
(a)
Aluminium
(b)
Nickel
Q2. The word box contains the names of some metals.
zinc
copper
iron
magnesium
silver
sodium
(a)
Identify the metal which is made in a blast furnace.
(a) Iron
(b)
Identify the two metals that do not react with acid.
(b) Copper and silver
(c)
Identify the two metals that can be used in sacrificial
(c) Zinc and magnesium
(d) Sodium
protection of iron.
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(d)
Identify the metal which reacts rapidly with water forming
Units 11 and 12 Revision
Q3. Copper can be mixed with other metals to produce alloys for different uses.
Aluminium is added to copper to make an alloy suitable for aircraft bodies.
Coins are made from a hard wearing alloy which contains copper and nickel.
Musical instruments can be made from an alloy of copper and zinc.
If tin is added to copper can be used to make ship’s propellers.
(a) Present this information in a table with suitable headings.
(b) Copper metal is a finite resource.
What is meant by the term ‘finite resource’?
(a)
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Metals in alloy
Use of alloy
copper and aluminium
aircraft bodies
copper and nickel
coins
copper and zinc
musical instruments
copper and tin
ship’s propellers
(b) A finite resource is a material whose supply will run out some time in the
future.
Units 11 and 12 Revision
Q 4. The reactivity of metals can be compared by adding them to a mixture of hydrochloric
acid and detergent.
Amy set up five test tubes each containing a different metal.
(a) Name the gas produced when a metal reacts with hydrochloric acid.
(b) Suggest a name for metal X.
(You may wish to use page 7 of the data booklet).
(c) Name one factor which would have to be kept the same to ensure a fair
comparison.
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(a)
Hydrogen.
(b)
Copper or silver or gold.
(c) Concentration of acid, temperature and size of piece of metal.
Units 11 and 12 Revision.
Q5. Hot magnesium ribbon reacts vigorously with steam. It glows very brightly
and the products are magnesium oxide and hydrogen gas.
(a) Write a balanced equation, using symbols and formulae, for the reaction taking
place in the test tube.
(b) The magnesium oxide which is formed will react with dilute hydrochloric acid.
Name the type of chemical reaction which takes place.
(c) Name the salt formed when magnesium oxide reacts with hydrochloric acid.
(d) Name the product formed when hydrogen burns.
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 2MgO
(a)
2Mg + O2
(b)
Neutralisation.
(c)
Magnesium chloride.
(d)
Water.
Units 11 and 12 Revision.
Q6. The diagram shows some ways in which iron can be protected from rusting
.
galvanising
painting
IRON
alloying
sacrificial
protection
(a) Name a metal which is suitable for the sacrificial protection of iron.
(b) Which metal is used to galvanise iron?
(c) How does painting prevent the rusting of iron.
(d) Alloys of iron are called steels.
Name another alloy.
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(a)
Magnesium or zinc.
(b)
Zinc
(c)
Paint stops air or water getting to the surface of the iron.
(d)
Brass, bronze, solder are a few examples of alloys.
Units 11 and 12 Revision.
Q7. Wilma investigated the reaction of the metals R, S and T with water.
hydrogen
hydrogen
beaker
water
filter
funnel
Metal R
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Metal S
Metal T
(a)
Place the metals in order of reactivity (most reactive first)
(b)
Identify a variable that Wilma would have kept constant.
(c)
Why is it unsafe to use potassium metal in this experiment?
(d)
How would Wilma test the gas to show that it was hydrogen?
(a)
T R S.
(b)
Water temperature, size size of metals.
(c)
Potassium is too reactive –there could be an explosion.
(d) The hydrogen gas burns with a ‘pop’.
Units 11 and 12 Revision.
Q8. Metals and their compounds take part in many reactions.
A
Fe 2 O 3 + 3CO
2Fe +
3CO 2
B
2M g + SiO 2
2M g O
+ Si
C
Cu CO 3
D
2Zn
+ O2
Cu O
+ CO 2
2Zn O
Which of the reactions, A to D, shows
(a) Reaction B (Silicon)
(a)
The reaction which produces a non-metal element
(b)
The reaction which takes place in the blast furnace.
(b) Reaction A.
Q9. (a) Calculate the percentage by mass of aluminium in aluminium oxide,
Al2O3.
(a) 52.9%
(b) Explain why aluminium cannot be obtained from aluminium oxide
by heating with carbon.
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(b)
Aluminium forms very strong bonds with oxygen. Heating with
carbon does not provide enough energy to break these bonds.
Units 11 and 12 Revision.
Q10. Some Euro coins are made from a hard-wearing alloy called Nordic Gold.
(a) What is an alloy?
(a) Mixture of
(b) The composition of Nordic Gold is shown in the table.
Metal
% by mass
copper
aluminium
89
5
zinc
tin
5
1
One of the coins has a mass of 5.74 g.
metals.
(b) (i) 0.287 g
(i) Calculate the mass, in grams, of aluminium in the coin.
(ii) 0.011 mol
(ii) Calculate the number of moles of aluminium in the coin.
Q11. Titanium is obtained from titanium(IV) chloride, TiCl4.
Given that titanium has a relative atomic mass of 48, calculate the
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percentage of titanium in titanium(IV) chloride.
25.26%
Units 11 and 12 Revision.
Q12. Oil rigs made from iron should be protected from rusting.
Identify the two correct statements.
A
Salt water slows down rusting
B
Tin gives sacrificial protection to the iron.
C
The rusting of iron is an example of oxidation
D
Ferroxyl indicator turns blue in the presence of Fe2+ ions.
E
Iron rusts faster when connected to the negative terminal of a battery.
C and D are correct statements.
Q13. Equations are used to represent chemical reactions.
 2H2O(g)
A
2H2(g) + O2 (g)
B
Zn(s) + FeSO4(aq)
C
Fe2+(aq)
D
CH4(g) + 2O2 (g)
E
2H2O(l + O2 (g) + 4 e-
F
Fe2+(aq) + 2e-


Fe3+(aq)

Fe(s)
+ ZnSO4(aq)
+ eCO2 (g) + H2O(g)

4OH-(aq)
 Fe(s)
Identify the two equations which represent a step in the rusting of iron.
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C and E
Units 11 and 12 Revision.
Q14. Some metals are found uncombined in the Earth’s crust but others have to be extracted
from their ores.
(a)
lead
magnesium, mercury
Which of these metals
(a) (i) magnesium
(i) can only be obtained by electrolysis of its molten ore?
(ii) mercury
(ii) can be obtained from its ore by heat alone?
(iii) lead.
(iii) can be obtained from its ore by heating with carbon?
(b) Iron is extracted by reacting iron(III) oxide with carbon monoxide.
(i) Name the type of industrial plant where iron is extracted.
(ii) The overall reaction taking place during the extraction of iron is given by
the equation:
Fe2O3
+
3CO
 2Fe
+ 3CO2
Calculate the mass of iron, in tonnes, which is produced from 1600 tonnes of
iron(III) oxide.
1 mole of iron(III) oxide  2 moles of iron
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160g of iron(III) oxide  112 g of iron
So 1600 tonnes of iron(III) oxide  1120 tonnes of iron
Units 11 and 12 Revision.
Q15. Iron can be coated with different materials which provide a physical barrier
against corrosion.
A
tin
B
grease
C
paint
(a)
E (zinc)
D
plastic
(b)
A (tin)
E
zinc
(a) Identify the coating which also provides sacrificial protection.
(b) Identify the coating which, if scratched, would cause the iron to rust faster
than normal.
Q16. Iron can be protected against corrosion by
(a) connecting to magnesium.
(b) connecting to the negative terminal of a power supply.
Explain how both these methods of protection work.
(a) Both methods involve electrons being pushed on to iron which stops it
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rusting.
Units 11 and 12 Revision.
Q.17 Siobhan carried out some experiments with four metals (W,X,Y and Z) and some of
their compounds. She made the following observations.
(a) Name the gas formed when metal Y reacts with water.
(a) Hydrogen.
(b) Suggest names for metals W and Y.
(b) W = silver or mercury.
(c) Place the metals (W,X,Y and Z) in order of reactivity
(most reactive first).
d) Name the type of chemical reaction which takes place when
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a metal is extracted from its oxide.
Y = sodium, lithium,
potassium or calcium.
(c) Y, X,Z,W
(d) Reduction.
Units 11 and 12 Revision.
The diagram shows how an object can be coated in nickel.
The following reactions take place at the electrodes
Negative electrode:- Ni2+(aq) + 2e-  Ni(s)
Positive electrode:- Ni(s)  Ni2+(aq) + 2eIdentify the two correct statements.
A
Nickel ions move towards the nickel electrode.
B
The mass of the nickel electrode decreases.
C
The process is an example of galvanising.
D
Oxidation occurs at the nickel electrode.
E
Electrons flow through the solution.
B and D
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