WEST AFRICAN EXAMINATIONS COUNCIL (WAEC) GCE STYLE
2026 CHEMISTRY MOCK EXAMINATION
Objective, Essay and Alternative to Practical Work Questions and Answers
Independently Produced Practice Paper for Revision Purposes
This is a 100% original mock examination prepared strictly with reference to the current WAEC Chemistry syllabus for practice purposes. It is not a WAEC past question paper, it does not reproduce any official WAEC document, and it does not claim to predict or represent the actual WAEC examination in any way.
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General Instructions
1. This paper consists of three sections: Section A (Objective, corresponding to Paper 1), Section B (Essay, corresponding to Paper 2) and Section C (Alternative to Practical Work, corresponding to Paper 3).
2. Section A contains 60 objective questions. Answer ALL questions. Time: 50 minutes.
3. Section B contains 6 essay questions. Answer any FOUR (4) questions. Time: 1 hour 40 minutes.
4. Section C contains 2 compulsory questions on the Alternative to Practical Work. Answer BOTH questions. Time: 1 hour 45 minutes.
5. Total marks obtainable: 140 (60 marks for Section A, 40 marks for Section B and 40 marks for Section C).
6. Where relevant atomic masses are needed, they are given within the question. Write clearly and number your answers correctly.
SECTION A: OBJECTIVE QUESTIONS (60 MARKS)
Answer ALL questions. Each question carries 1 mark. Choose the correct option A, B, C or D.
1. The smallest particle of an element that can take part in a chemical reaction is called an
A. atom
B. molecule
C. ion
D. electron
2. The number of protons in the nucleus of an atom is called its
A. atomic number
B. mass number
C. isotopic number
D. valency
3. The sum of the number of protons and neutrons in the nucleus of an atom is called its
A. atomic number
B. mass number
C. valency
D. electron number
4. Atoms of the same element with the same atomic number but different mass numbers are called
A. isotopes
B. isomers
C. isobars
D. ions
5. The electronic configuration of a sodium atom (atomic number 11) is
A. 2,8,1
B. 2,8,2
C. 2,8,8
D. 2,9
6. Elements in the same group of the Periodic Table have similar chemical properties mainly because they have the same
A. number of protons
B. number of valence electrons
C. mass number
D. number of neutrons
7. Elements in the same period of the Periodic Table have the same number of
A. valence electrons
B. electron shells (energy levels)
C. protons
D. isotopes
8. The group of elements known as the noble gases is
A. Group I
B. Group VII
C. Group 0
D. Group IV
9. Which of the following is an alkali metal?
A. Sodium
B. Calcium
C. Aluminium
D. Chlorine
10. Which of the following is a halogen?
A. Sodium
B. Chlorine
C. Calcium
D. Neon
11. Chemical bonding formed by the complete transfer of electrons from one atom to another is called a(n)
A. ionic bond
B. covalent bond
C. metallic bond
D. hydrogen bond
12. Chemical bonding formed by the sharing of electron pairs between atoms is called a(n)
A. ionic bond
B. covalent bond
C. metallic bond
D. hydrogen bond
13. The bond present in metals, formed by a ‘sea’ of delocalised electrons around positive metal ions, is called a(n)
A. ionic bond
B. covalent bond
C. metallic bond
D. hydrogen bond
14. Which of the following compounds contains a predominantly ionic bond?
A. NaCl
B. CH4
C. H2O
D. CO2
15. Which of the following is a typical property of ionic compounds?
A. Low melting point
B. Good conductor of electricity when molten or in solution
C. Generally soft and flexible
D. Non-conductor of electricity in all states
16. The number of moles of a substance is calculated using the formula
A. moles = mass ÷ molar mass
B. moles = molar mass ÷ mass
C. moles = mass × molar mass
D. moles = molar mass – mass
17. Calculate the number of moles in 20 g of NaOH. (Molar mass of NaOH = 40 g/mol)
A. 0.5 mol
B. 1.0 mol
C. 2.0 mol
D. 0.25 mol
18. The volume occupied by one mole of any gas at standard temperature and pressure (s.t.p.) is approximately
A. 22.4 dm³
B. 24 dm³
C. 11.2 dm³
D. 1 dm³
19. Avogadro’s number, representing the number of particles in one mole of a substance, is approximately
A. 6.02 × 10²³
B. 3.01 × 10²³
C. 6.02 × 10²⁰
D. 1.00 × 10²³
20. Calculate the number of moles in 5.6 dm³ of a gas at s.t.p. (1 mole of gas occupies 22.4 dm³ at s.t.p.)
A. 0.25 mol
B. 0.5 mol
C. 1.0 mol
D. 2.0 mol
21. According to the Bronsted-Lowry theory, a substance that donates protons (H⁺) in a reaction is called a(n)
A. acid
B. base
C. salt
D. buffer
22. According to the Bronsted-Lowry theory, a substance that accepts protons (H⁺) in a reaction is called a(n)
A. acid
B. base
C. salt
D. buffer
23. The pH of a neutral solution at 25°C is
A. 0
B. 7
C. 14
D. 1
24. An acid that ionises almost completely in water, giving a pH close to 0 or 1, is described as a
A. strong acid
B. weak acid
C. strong base
D. weak base
25. Which of the following is a strong acid?
A. Hydrochloric acid (HCl)
B. Ethanoic acid (CH3COOH)
C. Carbonic acid (H2CO3)
D. Hydrocyanic acid (HCN)
26. Which of the following is a weak acid?
A. Hydrochloric acid
B. Nitric acid
C. Ethanoic acid
D. Sulphuric acid
27. The products formed when an acid reacts completely with a base are
A. a salt and water
B. a gas only
C. a salt only
D. an oxide only
28. A salt that contains a fixed number of water molecules within its crystal structure is called a
A. hydrated salt
B. anhydrous salt
C. double salt
D. basic salt
29. Which of the following reagents is used to test for the presence of carbon(IV) oxide gas, turning milky in its presence?
A. Limewater
B. Litmus paper
C. Universal indicator
D. Starch solution
30. The gas evolved when a metal carbonate reacts with a dilute acid is
A. carbon(IV) oxide
B. sulphur(IV) oxide
C. hydrogen
D. oxygen
31. In electrolysis, the electrode at which reduction (gain of electrons) occurs is called the
A. cathode
B. anode
C. electrolyte
D. salt bridge
32. In electrolysis, the electrode at which oxidation (loss of electrons) occurs is called the
A. cathode
B. anode
C. electrolyte
D. salt bridge
33. A substance that conducts electricity through the movement of ions, when molten or in solution, is called a(n)
A. electrolyte
B. insulator
C. metallic conductor
D. semi-conductor
34. During the electrolysis of molten sodium chloride, sodium metal is deposited at the
A. cathode
B. anode
C. both electrodes
D. neither electrode
35. The SI unit used to measure the quantity of electric charge is the
A. coulomb
B. ampere
C. volt
D. ohm
36. A cell that produces electrical energy directly from a spontaneous chemical reaction is called a
A. electrolytic cell
B. voltaic (galvanic) cell
C. capacitor
D. resistor
37. A chemical reaction that releases heat energy to the surroundings is described as
A. exothermic
B. endothermic
C. isothermic
D. adiabatic
38. A chemical reaction that absorbs heat energy from the surroundings is described as
A. exothermic
B. endothermic
C. isothermic
D. adiabatic
39. The minimum amount of energy required for a chemical reaction to occur is called the
A. activation energy
B. bond energy
C. ionisation energy
D. lattice energy
A. Decreasing the temperature of the solution
B. Increasing the concentration of the solution
C. Using larger pieces of the solid
D. Removing any catalyst present
41. A substance that speeds up a chemical reaction without itself being permanently changed is called a
A. catalyst
B. reactant
C. product
D. inhibitor
42. According to Le Chatelier’s principle, when a system at equilibrium is disturbed by a change in conditions, the system will shift in a direction that tends to
A. oppose or counteract the applied change
B. always favour the forward reaction only
C. always favour the backward reaction only
D. have no effect on the position of equilibrium
43. Increasing the pressure on a gaseous equilibrium system generally favours the side of the reaction with
A. fewer moles of gas
B. more moles of gas
C. an equal number of moles of gas
D. no gaseous species at all
44. Increasing the temperature of a system at equilibrium generally favours the
A. endothermic direction of the reaction
B. exothermic direction of the reaction
C. reactants only, regardless of the enthalpy change
D. products only, regardless of the enthalpy change
45. Organic compounds that contain only carbon and hydrogen atoms are called
A. hydrocarbons
B. carbohydrates
C. esters
D. alcohols
46. A hydrocarbon containing only single bonds between its carbon atoms is called a(n)
A. alkane
B. alkene
C. alkyne
D. arene
47. A hydrocarbon containing at least one carbon-carbon double bond is called a(n)
A. alkane
B. alkene
C. alkyne
D. arene
48. The general molecular formula for the alkane homologous series is
A. CnH2n+2
B. CnH2n
C. CnH2n-2
D. CnHn
49. The general molecular formula for the alkene homologous series is
A. CnH2n+2
B. CnH2n
C. CnH2n-2
D. CnHn
50. Which of the following is the first member of the alkane homologous series?
A. Methane
B. Ethane
C. Propane
D. Butane
51. The functional group -OH is characteristic of which class of organic compounds?
A. Alcohols
B. Aldehydes
C. Ketones
D. Carboxylic acids
52. The functional group -COOH is characteristic of which class of organic compounds?
A. Alcohols
B. Esters
C. Carboxylic acids
D. Ethers
53. The technique used to separate a mixture of miscible liquids with different boiling points is called
A. filtration
B. fractional distillation
C. decantation
D. simple evaporation
54. The technique used to separate an insoluble solid from a liquid in a suspension is called
A. filtration
B. distillation
C. chromatography
D. sublimation
55. The technique that separates the components of a mixture based on differences in their solubility between a stationary phase and a mobile phase is called
A. chromatography
B. crystallisation
C. filtration
D. decantation
56. The process by which a solid changes directly into a gas without passing through the liquid state is called
A. sublimation
B. evaporation
C. condensation
D. deposition
57. The gas law which states that, at constant temperature, the volume of a fixed mass of gas is inversely proportional to its pressure is known as
A. Boyle’s law
B. Charles’s law
C. Gay-Lussac’s law
D. Avogadro’s law
58. The gas law which states that, at constant pressure, the volume of a fixed mass of gas is directly proportional to its absolute temperature is known as
A. Boyle’s law
B. Charles’s law
C. Gay-Lussac’s law
D. Avogadro’s law
59. Which of the following gases is a major contributor to the greenhouse effect and global warming?
A. Oxygen
B. Carbon(IV) oxide
C. Nitrogen
D. Helium
60. The layer of the atmosphere that contains ozone, which helps protect the earth from harmful ultraviolet radiation, is called the
A. ozone layer (stratosphere)
B. troposphere only
C. exosphere
D. ionosphere only
SECTION A MARKING GUIDE: OBJECTIVE ANSWER KEY
Each correct answer carries 1 mark. Total = 60 marks.
| Q | Ans | Q | Ans | Q | Ans | Q | Ans |
| 1 | A | 16 | A | 31 | A | 46 | A |
| 2 | A | 17 | A | 32 | B | 47 | B |
| 3 | B | 18 | A | 33 | A | 48 | A |
| 4 | A | 19 | A | 34 | A | 49 | B |
| 5 | A | 20 | A | 35 | A | 50 | A |
| 6 | B | 21 | A | 36 | B | 51 | A |
| 7 | B | 22 | B | 37 | A | 52 | C |
| 8 | C | 23 | B | 38 | B | 53 | B |
| 9 | A | 24 | A | 39 | A | 54 | A |
| 10 | B | 25 | A | 40 | B | 55 | A |
| 11 | A | 26 | C | 41 | A | 56 | A |
| 12 | B | 27 | A | 42 | A | 57 | A |
| 13 | C | 28 | A | 43 | A | 58 | B |
| 14 | A | 29 | A | 44 | A | 59 | B |
| 15 | B | 30 | A | 45 | A | 60 | A |
SECTION B: ESSAY QUESTIONS (40 MARKS)
Answer any FOUR (4) questions only. Each question carries 10 marks.
1. (a) Define the term ‘mole’ as used in chemistry. (2 marks)
(b) Calculate the number of moles and the mass of carbon(IV) oxide, CO2, produced when 5 g of calcium trioxocarbonate(IV), CaCO3, decomposes completely on heating, according to the equation: CaCO3 -> CaO + CO2. [Ca = 40, C = 12, O = 16] (8 marks)
2. (a) 25.0 cm3 of 0.20 mol/dm3 sodium hydroxide solution, NaOH, exactly neutralised 20.0 cm3 of a hydrochloric acid solution, HCl, of unknown concentration. Calculate the concentration of the hydrochloric acid solution in mol/dm3. (7 marks)
(b) Write the balanced chemical equation for the reaction and state the type of reaction that occurred. (3 marks)
3. An element X has atomic number 17.
(a) Write the electronic configuration of X. (2 marks)
(b) State the group and period to which X belongs in the Periodic Table, giving a reason for each. (5 marks)
(c) State, with a reason, whether X is a metal or a non-metal. (3 marks)
4. (a) Distinguish between an exothermic reaction and an endothermic reaction, giving one example of each. (5 marks)
(b) Using the collision theory, explain why an increase in temperature generally increases the rate of a chemical reaction. (5 marks)
5. (a) Write the structural formula and name of the first three members of the alkane homologous series. (6 marks)
(b) State two chemical differences between alkanes and alkenes. (2 marks)
(c) Write a balanced equation for the complete combustion of ethane, C2H6, in excess oxygen. (2 marks)
6. (a) Define electrolysis. (2 marks)
(b) With the aid of ionic half-equations, describe what happens at the cathode and at the anode during the electrolysis of molten lead(II) bromide, PbBr2, using inert electrodes. (6 marks)
(c) State one industrial application of electrolysis. (2 marks)
SECTION B MARKING GUIDE (ESSAY)
Each question carries 10 marks. Award marks as guided below for correct method and accurate final answers, giving credit for any other correct point or method not shown.
Question 1
(a) A mole is the amount of a substance that contains as many elementary particles (atoms, molecules or ions) as there are atoms in exactly 12 g of carbon-12, that is, 6.02 x 10^23 particles (Avogadro’s number). (2 marks for a reasonable, complete definition)
(b) Molar mass of CaCO3 = 40 + 12 + (16 x 3) = 40 + 12 + 48 = 100 g/mol (2 marks).
Number of moles of CaCO3 = mass / molar mass = 5 / 100 = 0.05 mol (2 marks).
From the equation, the mole ratio of CaCO3 to CO2 is 1:1, so number of moles of CO2 produced = 0.05 mol (2 marks).
Mass of CO2 = number of moles x molar mass of CO2 = 0.05 x [12 + (16 x 2)] = 0.05 x 44 = 2.2 g (2 marks).
Question 2
(a) Number of moles of NaOH used = concentration x volume (in dm3) = 0.20 x (25.0/1000) = 0.20 x 0.0250 = 0.00500 mol (3 marks).
From the equation NaOH + HCl -> NaCl + H2O, the mole ratio of NaOH to HCl is 1:1, so number of moles of HCl = 0.00500 mol (2 marks).
Concentration of HCl = number of moles / volume (in dm3) = 0.00500 / (20.0/1000) = 0.00500 / 0.0200 = 0.25 mol/dm3 (2 marks).
(b) NaOH(aq) + HCl(aq) -> NaCl(aq) + H2O(l) (2 marks). This is a neutralisation reaction between a base and an acid, producing a salt and water (1 mark).
Question 3
(a) Electronic configuration of X (atomic number 17): 2, 8, 7 (2 marks).
(b) Group: X belongs to Group VII (the halogens), because it has 7 electrons in its outermost shell (valence shell) (2.5 marks). Period: X belongs to Period 3, because its electrons are arranged in three main energy levels/shells (2.5 marks).
(c) X is a non-metal (1.5 marks), because it has 7 valence electrons and therefore tends to gain one electron to attain a stable noble gas configuration, a typical behaviour of non-metals, rather than losing electrons as metals do (1.5 marks).
Question 4
(a) An exothermic reaction is one in which heat energy is released to the surroundings, so the temperature of the surroundings rises; an example is the combustion of a fuel such as methane. An endothermic reaction is one in which heat energy is absorbed from the surroundings, so the temperature of the surroundings falls; an example is the thermal decomposition of calcium trioxocarbonate(IV) (CaCO3) on heating. (5 marks: 2 marks for each correct definition, 0.5 mark for each valid example)
(b) An increase in temperature increases the average kinetic energy of the reacting particles, causing them to move faster (1.5 marks). This results in more frequent collisions between reacting particles per unit time (1.5 marks). It also increases the proportion of particles that possess energy equal to or greater than the activation energy required for a reaction to occur (1 mark). As a result, a greater proportion of collisions are successful (effective) collisions that lead to a reaction, so the overall rate of reaction increases (1 mark).
Question 5
(a) Any three members at 2 marks each (1 mark for correct structural formula, 1 mark for correct name): Methane, CH4; Ethane, CH3-CH3 (C2H6); Propane, CH3-CH2-CH3 (C3H8).
(b) Any two differences at 1 mark each: Alkanes are saturated hydrocarbons containing only single carbon-carbon bonds, while alkenes are unsaturated hydrocarbons containing at least one carbon-carbon double bond; alkanes generally undergo substitution reactions, while alkenes readily undergo addition reactions; alkenes decolourise bromine water/undergo addition with bromine, while alkanes do not readily react with bromine water in the absence of light or a catalyst.
(c) Balanced equation: 2C2H6(g) + 7O2(g) -> 4CO2(g) + 6H2O(l) (2 marks for a correctly balanced equation).
Question 6
(a) Electrolysis is the chemical decomposition of an electrolyte (an ionic compound in the molten state or in solution) by the passage of an electric current through it. (2 marks)
(b) At the cathode (negative electrode), reduction occurs: lead(II) ions gain electrons and are discharged as molten lead metal. Half-equation: Pb2+(l) + 2e- -> Pb(l) (3 marks).
At the anode (positive electrode), oxidation occurs: bromide ions lose electrons and are discharged as bromine gas. Half-equation: 2Br-(l) -> Br2(g) + 2e- (3 marks).
(c) Any one valid application at 2 marks: Electrolysis is used in the extraction/purification of reactive metals such as aluminium and sodium from their molten ores/compounds; it is used in electroplating, to coat one metal with a thin layer of another metal for protection or decoration; it is used in the industrial production of chemicals such as chlorine and sodium hydroxide from brine (concentrated sodium chloride solution).
SECTION C: ALTERNATIVE TO PRACTICAL WORK (40 MARKS)
This section is designed as an Alternative to Practical Work paper for candidates who are unable to sit for the actual laboratory-based practical examination. Study the descriptions and specimen results provided below carefully, then answer all the questions that follow.
Answer BOTH questions in this section.
Question 1: Volumetric Analysis (20 marks)
You are provided with: Solution A, which is 0.10 mol/dm3 hydrochloric acid, HCl; and Solution B, which is a solution of sodium trioxocarbonate(IV), Na2CO3, of unknown concentration.
20.0 cm3 portions of Solution B were pipetted into a conical flask each time and titrated against Solution A from a burette, using methyl orange as indicator. The specimen results obtained are given in the table below.
| Trial 1 | Trial 2 | Trial 3 | |
| Final burette reading (cm3) | 24.60 | 25.00 | 25.50 |
| Initial burette reading (cm3) | 0.00 | 0.50 | 1.00 |
| Volume of A used (titre) (cm3) | 24.60 | 24.50 | 24.50 |
(a) State the colour change observed at the end-point when methyl orange indicator is used in this titration. (2 marks)
(b) Identify, with a reason, which of the three titre values above should be considered a rough (less reliable) titration. (2 marks)
(c) Calculate the average volume of Solution A used, based on the concordant (closely agreeing) titre values. (3 marks)
(d) Write the balanced chemical equation for the reaction between Solution A and Solution B. (2 marks)
(e) Calculate the concentration of Solution B in mol/dm3. (6 marks)
(f) Calculate the concentration of Solution B in g/dm3. [Na = 23, C = 12, O = 16] (3 marks)
(g) State one precaution that should be taken to obtain accurate results in a titration experiment of this type. (2 marks)
Question 2: Qualitative Analysis (20 marks)
You are provided with the results of a series of tests carried out on a solid salt, Q, and its aqueous solution, as recorded by a candidate. Study the observations and inferences given in the table below, then answer the questions that follow.
| Test | Observation |
| (i) A small amount of solid Q was heated strongly in a dry test tube. | A colourless liquid condensed on the cooler parts of the tube, followed by the evolution of a colourless, choking gas that turned moist blue litmus paper red. On further/prolonged heating, the residue turned reddish-brown. |
| (ii) Aqueous NaOH was added, a little at first and then in excess, to a solution of Q. | A dirty (greenish) precipitate formed with a little NaOH; the precipitate did not dissolve when excess NaOH was added, and it slowly turned brown on standing in air. |
| (iii) Dilute HCl was added to a fresh portion of the solution of Q, followed by the addition of aqueous BaCl2. | A white precipitate formed, which did not dissolve when excess dilute HCl was added. |
| (iv) A fresh portion of the solution of Q was acidified with dilute H2SO4, and a few drops of acidified KMnO4 solution were added. | The purple colour of the KMnO4 solution was decolourised. |
(a) Identify the cation present in Q. (2 marks)
(b) Identify the anion present in Q. (2 marks)
(c) State the name of the salt Q. (2 marks)
(d) State one observation from Test (i) that suggests Q is a hydrated salt. (2 marks)
(e) Write the ionic equation for the reaction that occurred in Test (ii). (3 marks)
(f) Write the ionic equation for the reaction that occurred in Test (iii). (3 marks)
(g) Write the half-equation showing the oxidation that occurs in Test (iv). (3 marks)
(h) State the property of the cation in Q that is demonstrated by the result of Test (iv). (3 marks)
SECTION C MARKING GUIDE (ALTERNATIVE TO PRACTICAL WORK)
Award marks as guided below, giving credit for any other correct and chemically valid working, equation, or observation not listed.
Question 1: Volumetric Analysis
(a) Colour change at the end-point: the solution changes from yellow to orange/pink (a distinct colour change to pink/orange-red), which marks the end-point of the titration. (2 marks)
(b) Trial 1 (titre = 24.60 cm3) should be considered the rough titration, because its value differs from the other two titre values (24.50 cm3 and 24.50 cm3) by more than 0.10 cm3, whereas the other two are concordant (agree closely with each other). (2 marks)
(c) Average volume of A used = (24.50 + 24.50) / 2 = 24.50 cm3, using only the two concordant titre values from Trials 2 and 3. (3 marks)
(d) Na2CO3(aq) + 2HCl(aq) -> 2NaCl(aq) + H2O(l) + CO2(g) (2 marks for a correctly balanced equation).
(e) Number of moles of HCl used = concentration x volume (in dm3) = 0.10 x (24.50/1000) = 0.10 x 0.02450 = 0.00245 mol (2 marks).
From the equation, the mole ratio of Na2CO3 to HCl is 1:2, so number of moles of Na2CO3 = 0.00245 / 2 = 0.001225 mol, present in the 20.0 cm3 (0.0200 dm3) portion of Solution B used (2 marks).
Concentration of Solution B = number of moles / volume (in dm3) = 0.001225 / 0.0200 = 0.06125 mol/dm3, which may be rounded to 0.0613 mol/dm3 (2 marks).
(f) Molar mass of Na2CO3 = (23 x 2) + 12 + (16 x 3) = 46 + 12 + 48 = 106 g/mol. Concentration in g/dm3 = concentration in mol/dm3 x molar mass = 0.06125 x 106 = 6.49 g/dm3 (approximately) (3 marks).
(g) Any one valid precaution at 2 marks: Reading the burette at eye level to avoid parallax error; adding the acid drop by drop near the end-point to accurately detect the colour change; rinsing the pipette and burette with the appropriate solutions before use; ensuring no air bubbles are trapped in the burette tip before starting the titration; repeating the titration to obtain at least two concordant results.
Question 2: Qualitative Analysis
(a) The cation present in Q is the iron(II) ion, Fe2+. (2 marks)
(b) The anion present in Q is the sulphate(VI) ion, SO4(2-). (2 marks)
(c) The salt Q is iron(II) sulphate (ferrous sulphate), FeSO4. (2 marks)
(d) The observation that a colourless liquid (water) condensed on the cooler parts of the tube on heating indicates that Q contains water of crystallisation and is therefore a hydrated salt. (2 marks)
(e) Fe2+(aq) + 2OH-(aq) -> Fe(OH)2(s), forming the dirty green precipitate of iron(II) hydroxide (3 marks). (Credit may also be given for a correctly written equation showing the subsequent slow oxidation of Fe(OH)2 to Fe(OH)3 in air.)
(f) Ba2+(aq) + SO4(2-)(aq) -> BaSO4(s), forming the white precipitate of barium sulphate, which is insoluble in dilute acids (3 marks).
(g) Fe2+(aq) -> Fe3+(aq) + e-, showing the oxidation of iron(II) ions to iron(III) ions, which is accompanied by the reduction and decolourisation of the purple KMnO4 (acting as an oxidising agent) (3 marks).
(h) Test (iv) demonstrates that the Fe2+ ion is a reducing agent, since it is oxidised to Fe3+ while reducing (decolourising) the acidified KMnO4 solution (3 marks).
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