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The diagram shows part of the structures of five substances, A, B, C, D and E.
(a) Answer the following questions about these structures. Each structure may be used once, more than once or not at all.
(i) Which two of these structures, A, B, C, D or E, are compounds?
..................................................... and ................................................................. [2]
(ii) Which one of these structures, A, B, C, D or E, is monatomic?
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(iii) Which one of these structures, A, B, C, D or E, conducts electricity when solid?
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(iv) Which one of these structures, A, B, C, D or E, is the main constituent of natural gas?
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(v) Which one of these structures, A, B, C, D or E, is a solid which is soluble in water?
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(vi) Which one of these structures, A, B, C, D or E, is a hydrocarbon?
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(b) Substance E is present in air. Air is a mixture of different gases. Describe two characteristics of a mixture.
1 ...................................................................................................................................
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2 ...................................................................................................................................
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This question is about iron and iron compounds.
(a) Iron can be extracted from iron ore by reduction with carbon in a blast furnace.
(i) Which one of these substances is an ore of iron?
Draw a circle around the correct answer.
bauxite graphite hematite limestone [1]
(ii) The equation shows one of the reactions occurring in the blast furnace.
$$ 2Fe_2O_3 + 3C \rightarrow 4Fe + 3CO_2 $$
How does this equation show that $Fe_2O_3$ is reduced?
...............................................................................................................................
............................................................................................................................... [1]
(iii) The carbon dioxide formed can be reduced by carbon.
$$ CO_2 + C \rightarrow 2CO $$
The energy level diagram for this reaction is shown.
Explain how this diagram shows that the reaction is endothermic.
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(iv) Explain why iron is extracted by reduction with carbon and not by electrolysis.
Refer to the position of iron in the reactivity series in your answer.
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(b) Describe three properties of iron that show that it is a transition element and not a Group I element.
1 ...............................................................................................................................
2 ...............................................................................................................................
3 ............................................................................................................................... [3]
(c) Iron reacts with chlorine to form iron(III) chloride, $Fe_2Cl_6$.
(i) Balance the chemical equation for this reaction.
.....Fe + .....Cl_2 \rightarrow Fe_2Cl_6 [2]
(ii) At 400°C $Fe_2Cl_6$ molecules decompose.
$$ Fe_2Cl_6 \leftrightarrows 2FeCl_3 $$
What is meant by the symbol $\leftrightarrows$?
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(d) The structure of an ion is shown.
Deduce the molecular formula of this ion to show the number of iron, carbon and nitrogen atoms.
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The table shows the percentage by mass of the elements in the oceans and in the biosphere. The biosphere is all living organisms.
[Table_1]
(a) Answer these questions using only the information in the table.
(i) Deduce the percentage by mass of other elements present in the biosphere.
.............................. % [1]
(ii) Which metallic element is present in the oceans in the greatest percentage by mass?
................................................................................................................................................ [1]
(iii) Give two major differences in the percentage by mass of the elements in the oceans and in the biosphere.
1 ..............................................................................................................................................
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2 ..............................................................................................................................................
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(b) Living organisms respire. Water is produced during respiration.
(i) Name the other product of respiration.
................................................................................................................................................ [1]
(ii) Describe a chemical test for water.
test .............................................................................................................................................
observations ................................................................................................................................ [2]
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This question is about chlorine and compounds of chlorine.
(a) Use the kinetic particle model to describe the arrangement and type of motion of the molecules in:
• solid chlorine .............................................................................................................................................
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• chlorine gas. .................................................................................................................................................
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(b) The graph shows how the pressure of chlorine gas changes when temperature increases. The volume is kept constant.
[Image_1: Graph showing pressure of chlorine gas vs temperature]
Describe how the pressure of the chlorine gas changes with temperature.
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........................................................................................................................................................................ [1]
(c) (i) Complete the word equation to show the halogen and halide compound which react to form the products iodine and sodium chloride.
[Box Diagram showing placeholders for reactants and products resulting in iodine and sodium chloride formation]
...................... + ...................... $\rightarrow$ iodine + sodium chloride
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[2]
(ii) Explain, in terms of the reactivity of the halogens, why aqueous bromine will not react with aqueous sodium chloride.
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(d) Chlorine reacts with warm turpentine, $C_{10}H_{16}$.
Balance the chemical equation for this reaction.
$C_{10}H_{16} + 8Cl_2 \rightarrow .....C + ....HCl$ [2]
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(a) (i) Draw a circle around the carboxylic acid functional group in this structure. [1]
(ii) How many different types of atom are shown in this structure?
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(b) The melting point of pure $S$ is $159^\circ\text{C}$.
The boiling point of pure $S$ is $200^\circ\text{C}$.
(i) What is the physical state of pure $S$ at $100^\circ\text{C}$?
Explain your answer.
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(ii) Which one of these statements about an impure sample of compound $S$ is correct?
Tick one box.
\[\begin{array}{l}
\text{The melting point of impure } S \text{ is } 159^\circ \text{C and the boiling point is above } 200^\circ \text{C.}\\
\text{The melting point of impure } S \text{ is below } 159^\circ \text{C and the boiling point is } 200^\circ \text{C.}\\
\text{The melting point of impure } S \text{ is } 159^\circ \text{C and the boiling point is } 200^\circ \text{C.}\\
\text{The melting point of impure } S \text{ is below } 159^\circ \text{C and the boiling point is above } 200^\circ \text{C.}
\end{array}\] [1]
(c) Aqueous ethanoic acid has chemical properties which are typical of acids.
Describe two chemical properties of aqueous ethanoic acid.
1 ................................................................................................................................
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2 ................................................................................................................................
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(d) Ethanol can be converted into ethene by passing ethanol vapour over a catalyst of aluminium oxide.
\( \text{C}_2\text{H}_5\text{OH} \rightarrow \text{C}_2\text{H}_4 + X \)
(i) Identify compound $X$.
....................................................................................................................................... [1]
(ii) Explain why a catalyst is used.
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(iii) Draw the structure of a molecule of ethanol. Show all of the atoms and all of the bonds. [1]
(e) Ethene can be polymerised.
(i) State the name of the polymer formed from ethene.
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(ii) Terylene is also a polymer.
State one use of Terylene.
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This question is about zinc and compounds of zinc.
(a) Describe how you could prepare a pure sample of crystals of hydrated zinc sulfate using dilute sulfuric acid and an excess of zinc.
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(b) The equation shows the effect of heat on anhydrous zinc sulfate.
$ \text{ZnSO}_4 \xrightarrow{\text{heat}} \text{ZnO} + \text{SO}_3 $
(i) What type of chemical reaction is this? Tick one box.
[ ] addition
[ ] decomposition
[ ] displacement
[ ] oxidation
[1]
(ii) When 12.60 g of anhydrous zinc sulfate is heated, the mass of zinc oxide formed is 6.34 g. Calculate the mass of zinc oxide formed when 63.0 g of anhydrous zinc sulfate is heated.
mass of zinc oxide = ................................ g [1]
(c) Complete the table to calculate the relative formula mass of anhydrous zinc sulfate, ZnSO$_4$.
Use your Periodic Table to help you.
[Table_1]
relative formula mass = ................................ [2]
(d) Complete the table to show the number of electrons, protons and neutrons in the sulfur atom and zinc ion shown.
[Table_2]
[4]
(e) An alloy contains zinc, copper and aluminium. What is meant by the term alloy?
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................................................................................................................................. [1]
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A student investigates the rate of reaction of large pieces of magnesium carbonate with an excess of dilute nitric acid.
$$\text{MgCO}_3 + 2\text{HNO}_3 \rightarrow \text{Mg(NO}_3)_2 + \text{CO}_2 + \text{H}_2\text{O}$$
(a) Name the salt formed when magnesium carbonate reacts with dilute nitric acid.
.............................................. [1]
(b) The graph shows how the volume of carbon dioxide changes with time.
(i) After how many seconds did the reaction finish?
............................... s [1]
(ii) From the graph, deduce the volume of carbon dioxide produced during the first 50 seconds of the experiment.
............................... cm3 [1]
(iii) The experiment is repeated using smaller pieces of the same mass of magnesium carbonate. All other conditions are kept the same. Draw a line on the grid for the experiment using smaller pieces of magnesium carbonate. [2]
(iv) How does increasing the temperature affect the rate of this reaction? All other conditions are kept the same.
.............................................. [1]
(v) How does decreasing the concentration of nitric acid affect the rate of this reaction? All other conditions are kept the same.
.............................................. [1]
(c) Nitric acid contains nitrate ions. Complete these sentences about the test for nitrate ions using words from the list.
aluminium ammonia blue chloride copper green iron nitrate oxygen red
Aqueous sodium hydroxide and ............................... foil are added to the solution being tested. The mixture is warmed gently. The ............................... produced turns damp ............................... litmus paper ............................... . [3]
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(a) Lead compounds are pollutants in the air.
(i) State one source of lead compounds in the air.
(a) Lead compounds are pollutants in the air.
(ii) State one adverse effect of lead compounds on health.
(b) The table shows how easy it is to reduce four metal oxides with carbon.
[Table_1]
Use the information in the table to put the four metals in order of their reactivity.
Put the least reactive metal first.
(c) Part of the structure of graphite is shown.
Use the information from the diagram to explain why graphite is used as a lubricant.
(d) When carbon burns in a limited supply of air, a poisonous gas is formed.
Name this gas.
(e) When carbon is completely burned in air, carbon dioxide is formed.
Carbon dioxide forms a slightly acidic solution in water.
Which one of these pH values is the pH of a slightly acidic solution? Draw a circle around the correct answer.
pH 6 pH 7 pH 8 pH 10
(f) Carbon dioxide is a greenhouse gas.
(i) Name one other major greenhouse gas.
(f) Carbon dioxide is a greenhouse gas.
(ii) State one effect that greenhouse gases have on the environment.
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