Chemistry Exam Questions for SS3 First Term with Answers

You’re welcome to our school exams series where we provide you with termly examination questions in different subjects. In today’s post, we will focus on Chemistry exam questions. We will cover Chemistry exam questions for SS3 First term with answers. This means that we’ll be providing you with answers to the questions at the end. Also, you will get a few success tips on how to pass Chemistry examinations with flying colors. Remember to use the comments sections if you have questions, and don’t forget to join our Free Online Tutorial Classes on YouTube. (Subscribe to the Channel)

Introduction to Chemistry as a School Subject

Before we venture into Past Chemistry Exam Questions for SS3 First term, here’s a brief introduction to the subject:

Chemistry is a branch of science that deals with the study of matter — its composition, structure, properties, and the changes it undergoes. It helps students understand how substances interact and combine to form new materials.

As a school subject, Chemistry connects theory with practical experience. It teaches learners how to observe, experiment, and reason scientifically. Through Chemistry, students discover the principles behind everyday phenomena such as rusting, combustion, digestion, and the use of medicines.

Chemistry is also a foundation for careers in medicine, engineering, pharmacy, agriculture, and environmental science. Learning Chemistry develops critical thinking, problem-solving, and analytical skills that are useful in many aspects of life and future studies.

Chemistry Exam Questions for SS3 First Term

Chemistry Exam Questions for SS3 First Term are divided into two sections:

• Section A
• Section B

The first section, namely, Section A is the objective test, and students are expected to attempt all questions in the section. Section B is the theory part, and students are expected to follow specific instruction and answer the required number of questions.

Note that what you have below are SS3 Chemistry First Term Exam Past Questions made available to assist students in their revision for 1st term examinations and also teachers in structuring standard examinations.

SECTION A: Objective Test

Instruction: Answer all questions in this section by choosing from the options lettered A—D. Each question carries equal marks.

1. Which of the following polymers is a homopolymer?
A. Bakelite      B. Nylon-66
C. Terylene      D. Neoprene

2. When ethanol is exposed to air for a short time, the main reaction that occurs is:
A. C₂H₅OH → CH₃COOH (oxidation to ethanoic acid)
B. C₂H₅OH → CH₃CHO (oxidation to ethanal)
C. C₂H₅OH → C₂H₄ + H₂O (dehydration to ethene)
D. C₂H₅OH → CH₃–O–CH₃ (ether formation)

3. The number of naturally occurring α–amino acids is about:
A. 10        B. 50
C. 40        D. 20

4. Which statement best describes Le Chatelier’s principle?
A. A system at equilibrium will not change when disturbed
B. When a system at equilibrium is disturbed, it shifts to minimize the disturbance
C. Equilibrium constant (K) always increases with addition of reactant
D. Equilibrium position is independent of temperature

5. The impurities associated with an ore after mining are collectively called:
A. Flux              B. Slag
C. Minerals       D. Gangue

6. Which statement about alkali metals (Group 1) is correct?
A. They form covalent bonds with halogens
B. Their melting points decrease down the group
C. They form oxides when reacted with water
D. Their reactivity decreases down the group

7. The Rf value in paper chromatography is defined as:
A. Distance moved by solvent front / distance moved by solute spot
B. Distance moved by solute spot / distance moved by solvent front
C. Product of the two distances
D. Ratio of intensities of solute spots

8. The repeating unit of PTFE (polytetrafluoroethylene) is derived from which monomer?
A. Cl₂CH–CH₃
B. F₂C=CF₂ (tetrafluoroethylene)
C. F₃C–CF₃
D. FClC=CF₂

9. Aluminium is extracted commercially by:
A. Electrolysis of purified alumina
B. Reduction of the ore with coke in a furnace
C. Froth flotation of the smelted ore
D. Roasting the ore in excess air

10. Nylon-66 is prepared by condensation of:
A. Vinyl chloride and formaldehyde
B. Adipic acid and methylamine
C. Adipic acid and hexamethylenediamine
D. Formaldehyde and melamine

11. Which of the following is NOT a polymer?
A. Sucrose      B. Enzyme
C. Starch         D. Teflon

12. The polymer represented by (–NH(CH₂)₆–NHCO(CH₂)₄CO–)ₙ is:
A. A homopolymer
B. A copolymer
C. An addition polymer
D. A thermosetting polymer

13. Which of the following is a ketohexose?
A. Fructose       B. Maltose
C. Glucose        D. Ribose

14. Which polymer has the same type of linkage as fats (ester linkage)?
A. Polyamide     B. Polyester
C. Protein          D. Starch

15. The monomer of poly(chloroethene) (PVC) is:
A. Ethylene
B. Tetrafluoroethylene
C. Chloroethene (vinyl chloride)
D. None of the above

16. Dehydration of carbohydrate by concentrated H₂SO₄ gives:
A. A black residue of carbon
B. The component monosaccharides
C. A soot-like coal residue
D. A yellow–brown caramel

17. Which metal oxide can be reduced to the metal using carbon in a furnace?
A. CaO        B. MgO
C. Na₂O       D. ZnO

18. Which of the following processes does NOT produce both CO₂ and H₂O?
A. Addition of acid to a carbonate
B. Burning ethanol
C. Burning methane
D. Heating hydrated Na₂CO₃

19. Which of these is the correct property of an ester?
A. Esters are basic and react with acids to form salts
B. Esters have pleasant fruity smells and are formed from alcohol + carboxylic acid
C. Esters are ionic compounds
D. Esters are formed by addition of water to alkenes

20. The monomer used to make a polymer with fragment –CH₂–CH₂–CH₂–CH₂–CH₂–CH₂– is most likely:
A. C₂H₄         B. C₂H₆
C. C₃H₆         D. C₃H₈

21. Which of the following is NOT a condensation polymer?
A. Glyptal
B. Nylon-66
C. Dacron (Terylene)
D. PTFE (Teflon)

22. Which substance is amphoteric?
A. Na₂O       B. Al₂O₃
C. CaO         D. MgO

23. Which gas in air participates directly in oxidation of ethanol to vinegar?
A. Carbon dioxide
B. Nitrogen
C. Oxygen
D. Water vapour

24. Which of the following metals is extracted by smelting with carbon monoxide?
A. Aluminium
B. Magnesium
C. Iron
D. None of these

25. The great affinity of aluminium for oxygen at high temperatures is used in:
A. Hall–Héroult process
B. Thermite process
C. Haber process
D. Lead chamber process

26. In the froth flotation process, ore particles float because:
A. They are light
B. Their surface is not easily wetted by water
C. They are charged
D. They are insoluble

27. The main gases that escape from the blast furnace top are:
A. CO, CO₂ and H₂
B. N₂, CO₂ and CO
C. N₂, O₂ and H₂O
D. O₂, CO₂ and SO₂

28. Iron is paramagnetic because:
A. Orbitals have few unpaired electrons
B. Orbitals have only paired electrons
C. It has many unpaired electrons
D. It is ferromagnetic

29. The primary product when ethanol is dehydrated with conc. H₂SO₄ at 180°C is:
A. Ethane
B. Ethene
C. Diethyl ether
D. Ethanal

30. The polymer used to make soft drink bottles is:
A. Polyester
B. Polyurethane
C. Polyurea
D. Polystyrene

31. Synthetic rubber is produced from butadiene by:
A. Cracking
B. Hydrogenation
C. Polymerization
D. Vulcanization

32. In the blast furnace, which substance removes earthy impurities?
A. Air
B. Carbon(II) oxide
C. Coke
D. Limestone

33. Which reagent tests for C=C bond?
A. Acidified K₂Cr₂O₇
B. Br₂ in CCl₄
C. Tollen’s reagent
D. Benedict’s solution

34. Which type of reaction forms soap from fats?
A. Hydrolysis
B. Polymerization
C. Fermentation
D. Substitution

35. Which of the following is an ester?
A. PVC          B. Soap
C. Starch       D. Terylene

36. Zinc is not regarded as a transition metal because:
A. It has no electrons in 3d orbitals
B. Its 3d orbitals are completely filled
C. It blends readily with neighbours
D. It does not form complex ions

37. The molecular formula of sucrose is:
A. CH₂O
B. C₆H₁₂O₆
C. C₁₂H₂₂O₁₁
D. CH₃COOH

38. During electrolysis of molten NaCl, the products are:
A. H₂ at cathode, Cl₂ at anode
B. Na at cathode, Cl₂ at anode
C. Na at anode, O₂ at cathode
D. H₂ at anode, O₂ at cathode

39. Steel is best described as:
A. Alloy of iron and carbon only
B. Alloy of iron, carbon, and other elements
C. Alloy of iron, carbon, and nickel
D. Alloy of iron, carbon, and chromium

40. When solid X gives off a gas that turns limewater milky, and residue reacts with acids and alkalis, X is likely:
A. CuCO₃        B. MgCO₃
C. Na₂CO₃       D. ZnCO₃

41. Which reagent converts alcohol to alkene by dehydration?
A. Cold dilute HCl
B. Concentrated H₂SO₄ (heat)
C. Benedict’s reagent
D. NaOH(aq)

42. Which polymer is a copolymer?
A. Polypropylene
B. Nylon-66
C. PVC
D. Teflon

43. Bakelite is obtained from phenol by reaction with:
A. Ethanol
B. Methanal (formaldehyde)
C. Vinyl chloride
D. Ethylene glycol

44. Which of these metals is NOT extracted by electrolysis?
A. Sodium      B. Aluminium
C. Calcium      D. Magnesium

45. Which disaccharide is present in milk?
A. Maltose     B. Galactose
C. Sucrose      D. Lactose

46. The dominant inter-particle forces in Nylon-66 are:
A. Hydrogen bonds
B. Covalent bonds
C. Ionic bonds
D. Van der Waals forces

47. What is produced when ethanol is boiled with excess acidified K₂Cr₂O₇?
A. Ethane
B. Ethanoic acid
C. Ethene
D. Ethyl ethanoate

48. The linkage that holds monosaccharide units together in a polysaccharide is:
A. Peptide linkage
B. Glycosidic linkage
C. Ester linkage
D. Ionic linkage

49. Which metal reacts with nitrogen to form Ca₃N₂?
A. Aluminium
B. Magnesium
C. Calcium
D. Zinc

50. Which polymerization type forms Nylon-66 and Terylene?
A. Addition
B. Condensation
C. Fermentation
D. Hydrolysis

51. Fats and oils are chemically:
A. Monoesters of glycerol
B. Diesters of glycerol
C. Triesters of glycerol
D. Diesters of glycol

52. The Rf value in chromatography is expressed as:
A. Distance moved by solute / distance moved by solvent front
B. Distance moved by solvent front / distance moved by solute
C. Product of both
D. Difference of both

53. Which of the following is a typical property of transition metals?
A. They form coloured compounds
B. They have low densities
C. They have low melting points
D. They react with cold water

54. Vinegar is obtained by oxidation of:
A. Methanol     B. Propanol
C. Ethanol         D. Butanol

55. A margarine labeled “high in polyunsaturates” contains molecules with:
A. Long-chain alkanes
B. Many C=C bonds
C. Alkynes
D. –O=C–N–H linkages

56. Which process gives black carbon residue from carbohydrate?
A. Hydrolysis
B. Fermentation
C. Dehydration by conc. H₂SO₄
D. Reduction

57. Bakelite is classified as:
A. Addition polymer
B. Elastomer
C. Thermoplastic
D. Thermosetting polymer

58. When ethanol is exposed to air for a very long time, it undergoes:
A. Oxidation to ethanoic acid
B. Partial oxidation to ethanal
C. Dehydration to ethene
D. Etherification

59. Which of the following best explains saponification?
A. Hydrolysis of fats to soap and glycerol
B. Dehydration of alcohol
C. Polymerization of ethene
D. Neutralization reaction

60. Part of a polymer chain is –CH₂–CH₂–CH₂–CH₂–CH₂–CH₂–. Its monomer is:
A. Ethene        B. Propene
C. Butene        D. Hexene

Read Also: Agricultural Science Exam Questions for SS3 First Term

SECTION B: Essay / Theory

INSTRUCTION – Answer only five (5) questions in this section. Write your answers clearly and show working where necessary.

1. (a) Define oxidation and reduction in terms of electron transfer and O/H change.
(b) Describe electrolysis of molten and aqueous ionic compounds with examples and products.
(c) Explain the effect of temperature on equilibrium (Le Chatelier’s principle).

2. (a) Distinguish between esterification and saponification reactions.
(b) Write structural formulas for an ester and its parent alcohol and acid.
(c) Describe two methods of preparing ethanoic acid using equations.
(d) Show reactions of ethanoic acid with NaHCO₃ and Zn.

3. (a) Explain with examples: Polyester and Polyamide.
(b) How does vulcanized rubber differ from natural rubber?
(c) Classify Terylene, Nylon-66, Neoprene and Teflon.
(d) Distinguish between homopolymer and copolymer.

4. (a) Describe how pure Al₂O₃ is obtained from bauxite (Bayer process).
(b) Explain why HNO₃ can be stored in aluminium containers.
(c) Name the purest form of iron and its property.
(d) Write balanced equations for major reactions in the blast furnace.
(e) List alloying elements in stainless steel and duralumin.

5. (a) State hydrolysis products of sucrose and lactose.
(b) Describe how NaOH can be prepared from Na₂CO₃ (with equation).
(c) Give equations for reactions of NaOH with Zn and Al.
(d) Mention four characteristic properties of transition metals.

6. (a) Describe two laboratory methods for preparing esters with reagents and conditions.
(b) Explain how to distinguish between primary, secondary and tertiary alcohols experimentally.

7. (a) Draw the structure of a synthetic detergent molecule and label parts.
(b) Draw structures of glycine and alanine.
(c) Explain: (i) Primary structure of proteins (ii) Denaturation.
(d) Give one example each of an aldohexose and aldotriose.
(e) Draw the structure of sucrose.

Remember to use the comments sections if you have questions, and don’t forget to join our Free Online Tutorial Classes on YouTube. (Subscribe to the Channel)

Answers to Chemistry Exam Questions for SS3 First Term

Answers to Section A (Objective Test)

The following table gives the correct answers to the objective section of Chemistry exam questions for SS3 First term. If you are using a mobile device, hold the table and scroll to the right or left for a complete view.

So here you have the answers to the objective section of Chemistry Exam Questions for SS3 First term. Use the comments section to let me know if you have any questions you would want me to clarify or discuss further.

Answers to Section B (Theory)

Answers to Question 1.

(a) Oxidation is the process in which an atom, ion, or molecule loses electrons or gains oxygen or loses hydrogen. Reduction is the gain of electrons, loss of oxygen, or gain of hydrogen.
Example:
Fe²⁺ → Fe³⁺ + e⁻ (oxidation)
Cl₂ + 2e⁻ → 2Cl⁻ (reduction)

(b) Electrolysis is the decomposition of a compound by passing electric current through it.

• Molten ionic compounds: For example, electrolysis of molten NaCl produces sodium at the cathode and chlorine gas at the anode.
  NaCl(l) → Na(l) + ½Cl₂(g)
• Aqueous ionic compounds: In aqueous NaCl, H₂ is discharged at the cathode and Cl₂ at the anode due to water competition.
  Cathode: 2H₂O + 2e⁻ → H₂ + 2OH⁻
  Anode: 2Cl⁻ → Cl₂ + 2e⁻

(c) According to Le Chatelier’s Principle, when a system at equilibrium is disturbed by temperature, pressure, or concentration change, the system shifts to counteract the disturbance.
If the forward reaction is endothermic, increasing temperature shifts equilibrium to the right; if exothermic, it shifts to the left.

Answers to Question 2.

(a) Esterification is the reaction between an alcohol and a carboxylic acid to form an ester and water, usually in the presence of conc. H₂SO₄.
Saponification is the hydrolysis of fats or oils (esters) with NaOH or KOH to produce soap and glycerol.

(b) Example:
Ethanol + Ethanoic acid → Ethyl ethanoate + Water
Structural formulas:
CH₃CH₂OH + CH₃COOH → CH₃COOCH₂CH₃ + H₂O

(c) Methods of preparing ethanoic acid:
1. Oxidation of ethanol:
CH₃CH₂OH + 2[O] → CH₃COOH + H₂O
2. Oxidation of acetaldehyde:
CH₃CHO + [O] → CH₃COOH

(d) Reactions:
CH₃COOH + NaHCO₃ → CH₃COONa + CO₂ + H₂O
2CH₃COOH + Zn → (CH₃COO)₂Zn + H₂

Answers to Question 3.

(a) Polyesters are polymers formed from dicarboxylic acids and diols, e.g. Terylene (from ethane-1,2-diol and benzene-1,4-dicarboxylic acid).
Polyamides are polymers formed from dicarboxylic acids and diamines, e.g. Nylon-66 (from adipic acid and hexamethylenediamine).

(b) Vulcanized rubber has sulfur bridges between polymer chains, making it tougher and more elastic than natural rubber.

(c) Classifications:
Terylene – Polyester
Nylon-66 – Polyamide
Neoprene – Synthetic rubber
Teflon – Addition polymer

(d) Homopolymer: made from one type of monomer (e.g. polyethylene).
Copolymer: made from two or more different monomers (e.g. nylon-66).

Answers to Question 4.

(a) In the Bayer process, bauxite is digested with hot concentrated NaOH, forming sodium aluminate. The solution is filtered and CO₂ is bubbled through to precipitate pure Al(OH)₃, which is heated to form Al₂O₃.
Al(OH)₃ → Al₂O₃ + 3H₂O

(b) HNO₃ can be stored in aluminium containers because aluminium forms a protective oxide layer (Al₂O₃) that resists corrosion.

(c) The purest form of iron is wrought iron; it is soft, malleable, and contains less than 0.2% carbon.

(d) Major blast furnace reactions:
C + O₂ → CO₂
CO₂ + C → 2CO
Fe₂O₃ + 3CO → 2Fe + 3CO₂

(e) Alloying elements:
Stainless steel – Fe, Cr, Ni
Duralumin – Al, Cu, Mg, Mn

Answers to Question 5.

(a) Hydrolysis products:
Sucrose → Glucose + Fructose
Lactose → Glucose + Galactose

(b) NaOH from Na₂CO₃:
Na₂CO₃ + Ca(OH)₂ → 2NaOH + CaCO₃↓

(c) Reactions:
2NaOH + Zn → Na₂ZnO₂ + H₂
2Al + 2NaOH + 6H₂O → 2Na[Al(OH)₄] + 3H₂

(d) Transition metals have:
1. Variable oxidation states
2. Form coloured compounds
3. Form complex ions
4. Act as catalysts

Answers to Question 6.

(a) Laboratory preparation of esters:

1. By heating carboxylic acid with alcohol and conc. H₂SO₄ – e.g. ethanoic acid + ethanol → ethyl ethanoate.
2. By reacting acid chloride with alcohol – e.g. CH₃COCl + C₂H₅OH → CH₃COOC₂H₅ + HCl.

(b) Distinguishing alcohols:

• Primary alcohols oxidize easily to aldehydes with acidified K₂Cr₂O₇ (orange to green).
• Secondary alcohols oxidize to ketones (colour change same).
• Tertiary alcohols do not react with oxidizing agents.

Answers to Question 7.

(a) Structure of a synthetic detergent:
Hydrophilic head (–SO₃⁻Na⁺) attached to a long hydrophobic hydrocarbon tail (R–).
Example: R–SO₃⁻Na⁺

(b) Structures:
Glycine: NH₂CH₂COOH
Alanine: CH₃CH(NH₂)COOH

(c) (i) Primary structure of proteins: Linear sequence of amino acids joined by peptide bonds.
(ii) Denaturation: Loss of protein’s natural structure due to heat or pH changes, causing loss of biological activity.

(d) Examples:
Aldohexose – Glucose
Aldotriose – Glyceraldehyde

(e) Structure of sucrose:
Glucose and fructose units joined by α,β-1,2-glycosidic linkage.

How to Pass Chemistry Exam Questions for SS3 First Term

Chemistry at the SS3 level requires more than just cramming definitions and equations. It demands clear understanding, smart study habits, and consistent practice. The following tips will help you pass your SS3 First Term Chemistry exam with confidence.

1. Study the Syllabus and Class Notes Thoroughly

Begin by reviewing your Chemistry syllabus to know the topics covered in the first term. Go through your class notes carefully and ensure that you understand key concepts such as organic chemistry, electrolysis, chemical equilibrium, and acid-base reactions. Don’t skip any topic taught by your teacher.

2. Master Chemical Equations and Calculations

Many Chemistry questions involve chemical equations and mole calculations. Practice writing and balancing equations regularly. Learn how to apply formulas in mole concept, molarity, and gas laws. The more you practice, the more confident you become in solving numerical problems during exams.

3. Use Recommended Textbooks and Past Questions

Study with WAEC- and NECO-approved Chemistry textbooks. After studying each topic, test yourself with past questions to know how examiners set questions. Past questions will also help you identify frequently tested areas and understand the marking scheme.

4. Understand Practical Chemistry

Don’t ignore the practical aspect of Chemistry. Learn how to identify unknown salts, perform titration calculations, and record observations correctly. Knowing how to write accurate inferences from experiments can give you a strong edge during your exams.

5. Create a Study Schedule and Revise Regularly

Distribute your study time wisely across different topics. Avoid last-minute reading. Instead, revise regularly to keep formulas, reactions, and concepts fresh in your memory. Group discussions can also help you understand difficult topics faster.

6. Pay Attention to Definitions and Chemical Terms

Many objective questions come from definitions and scientific terms. Learn precise definitions of terms like ionization energy, oxidation number, electronegativity, and activation energy. Always use standard scientific language in your exams.

7. Stay Calm and Manage Your Time During the Exam

Read instructions carefully before answering. Attempt the easier questions first to gain confidence. Manage your time wisely so you can attempt all questions before the bell rings. Stay calm and trust your preparation.

With steady preparation, consistent practice, and the right mindset, you can excel in your SS3 First Term Chemistry exam and lay a solid foundation for your WAEC and NECO examinations.

It’s a wrap!

If you need more clarification on SS3 First Term Questions on Chemistry, you can use the comments box below. We’ll be there to answer you asap. Don’t forget to join our Free Online Tutorial Classes on YouTube. (Subscribe to the Channel)

Best wishes..