Free WAEC Chemistry objective Past Questions and Answers (+PDF)

Need free WAEC Chemistry objective past questions to study now for your exam?

See the standard 50 WAEC objective Chemistry questions with answers and explanation or download 3 YEARS PDF at the bottom of this post for offline study.

• ALSO SEE: WAEC PAST QUESTIONS FOR OTHER SUBJECTS

Study WAEC Chemistry objective past questions

Click any heading (in red) for more WAEC questions on that topic or “SEE ANSWER” under each question.

WAEC

1. The shape of CH4 is _____

A. linear
B. planar
C. pyramidal
D. tetrahedral

WAEC literary device

2. The crystal layers in graphite are held together by _____

A. covalent bond
B. electrostatic forces
C. ionic bond
D. van der waals forces

WAEC poetry terms

3. Hydrogen bonds are formed between molecules containing a hydrogen atom bonded to a ____

A. strongly electronegativity atom
B. non-polar species
C. diatomic element
D. complex ion

WAEC drama terms

4. The two elements 11X and 19Y are in the same group because they have the same _____

A. valence electrons
B. ionization energy
C. number of shell
D. atomic size

WAEC poetry terms

5. Which of the following processes is used in food preservation in an industry?

A. Carbon dating
B. Radiation of gamma rays
C. Nuclear fission
D. Nuclear fusion

WAEC figures of speech

6. Which of the following arrangements is in decreasing order of atomic radius?

A. Li > Be > C > B
B. Li > B > Be > C
C. Li > Be > B > C
D. C > B > Be > Li

WAEC rhyme scheme

7. The electron configuration of 26𝐹𝑒3+ is _____

A. [Ar]4s23d6
B. [Ar]4s23d3
C. [Ar]4s13d4
D. [Ar]4s03d5

WAEC poetry terms

8. Which of the following transition metals is NOT attracted to external magnetic field?

A. Cu
B. Fe
C. Ti
D. Zn

WAEC drama terms

9. An atom W has 17 electrons and 18 neutrons. Which of the following representations of the atom is correct?

A. 1718W
B. 1817W
C. 3517W
D. 3518W

WAEC poetry terms

10. The relative atomic mass of chlorine is NOT a whole number because _____

A. it is the weighted average mass of all its various isotopes
B. it is the average mass of all the isotopes of the element
C. the element has strong oxidizing ability
D. the atom contains a higher number of neutrons than protons

WAEC rhyme scheme

11. NH4- is formed from NH3 and H+ by _____

A. covalent bonding
B. dative bonding
C. hydrogen bonding
D. ionic bonding

WAEC prose terms

12. How many lone pair(s) of electrons is present in HF?

A. 0
B. 1
C. 2
D. 3

WAEC literary device

13. An aqueous solution of Na2CO3 is _____

A. acidic
B. alkaline
C. amphoteric
D. neutral

WAEC literary device

14. A gaseous mixture contains 0.256g of hydrogen and 2.00g of oxygen. The mole ration of hydrogen to oxygen in the mixture is _____ [H=1.00; O=16.0]

A. 1:1
B. 2:1
C. 1:4
D. 8:1

WAEC figures of speech

15. If 0.20 mol dm-3 NaOH(aq) was evaporated to yield 5.0g of solid NaOH, calculate the volume of NaOH(aq) used. [Na=23.0, O=16:0; H=1.00]

A. 600 cm3
B. 625 cm3
C. 1000 cm3
D. 1600 cm3

WAEC drama terms

16. The oxidation number of sulphur in Fe2(SO4)3 is _____

A. +2
B. +3
C. +4
D. +6

WAEC poetry terms

17. The mass of 800cm3 of gas Q at s.t.p. is 1.0g. What is the molar mass of Q? [Avogadro constant = 22.4dm3 mol-1]

A. 18.0 gmol-1
B. 22.4 gmol-1
C. 28.0 gmol-1
D. 36.0 gmol-1

WAEC drama terms

18. A Compound U melts at 82oC  and boils at 113oC. If U was found to be insoluble in water, a mixture of U in water could best be separated by _____

A. Chromatography
B. Sublimation
C. Filtration
D. the use of separating funnel

WAEC figures of speech

19. The Following set-up can be used to demonstrate _____ 

A. Diffusion 
B. Dissolution 
C. Evaporation 
D. Sub-Limitation

WAEC literary device

20. Which of the following statements about a chemical system in equilibrium is correct? The _____

A. reaction is irreversible
B. reaction goes to completion
C. equilibrium is re-established when a stress is applied
D. equilibrium position is affected by catalyst

WAEC literary device

21. Which of the following relationships correctly expresses the Boyle's law?

A. P 𝛼 V at constant T
B. V 𝛼 T at constant P
C. P 𝛼 1/V at constant T
D. V 𝛼 1/T at constant P

WAEC figures of speech

22. The vapour pressure of a given volume of liquid increase when the _____

A. liquid becomes saturated with a salt
B. Volume of the liquid increases
C. temperature of the liquid falls
D. temperature of the Liquid rises

WAEC literary device

23. Which of the following statements about volatile liquids is correct? They have _____

A. high vapour pressure and low boiling point
B. high vapour pressure and high boiling point
C. low vapour pressure and low boiling point
D. low vapour pressure and high boiling point

WAEC figures of speech

24. The type of energy changes that accompany the mixing of a strong acid to a strong base is _____

A. electrical
B. heat
C. light
D. Sound

WAEC prose terms

25. Zinc oxide is said to be amphoteric because it _____

A. forms an acid salt
B. is an insoluble base
C. forms a double salt
D. reacts with a base or an acid

WAEC rhyme scheme

Which of the following substances with the corresponding pH value is an alkali? 

Substance 	         pH

A. Lime 		2.4
B. Banana 		4.6
C. Distilled water 	7.0
D. Milk of magnesia 	10.5

WAEC poetry terms

27. The gases produced when Cu(NO3)2(s) was heated are _____

A. NO and NO2
B. O2 and NO
C. NO2 and N2O4
D. O2 and NO2

WAEC literary device

28. Which of the following salts on hydrolysis would give an alkaline solution?

A. NH4Cl(s)
B. AlCl3(s)
C. CH3COONa(s)
D. NH4NO3(s)

29. Consider the reaction represented by the following equation: Na2CO3(aq) + 2HCl(aq) ⟶ 2NaCl(aq) + H2O(l) + CO2(g). What volume of 0.02moldm-3 Na2CO3(aq) would be required to completely neutralize 40cm3 of 0.10 moldm-3 HCl(aq)?

A. 200 cm3
B. 100 cm3
C. 40 cm3
D. 20 cm3

30. In which of the following experiment set-ups would the rate of evolution of hydrogen gas be fastest?

WAEC Shakespeare (The Tempest)

31. Which of the following factors would affect the equilibrium constant?

A. Concentration
B. Temperature
C. Pressure
D. Volume

WAEC Shakespeare (The Tempest)

32. Consider the following energy profile diagram of exothermic reaction. The enthalpy change, “H” is ____

A. 120 KJmol-1
B. 80 KJmol-1
C. 60 KJmol-1
D. 40 KJmol-1

33. Consider the reaction represented by the following equation: N2(g) + 3H2(g) ⇌ 2NH3(g); ∆Hϴ = -xkJmol-1. Which of the following conditions would increase the yield of NH3?

A. Addition of iron catalyst
B. Increase in the temperature of the system
C. Increase in the volume occupied by reactants
D. Increase in the total pressure of the system

34. What is the function of manganese (IV) oxide in the reaction represented by the following equation? MnO2 + 4HCl → MnCl2 + 2H2O + Cl2

A. Catalyst
B. Dehydrating agent
C. Oxidizing agent
D. Reducing agent

35. The reaction that occurs at the anode when CuSO4(aq) is electrolyte using carbon electrode is _____

A. 2H-(aq) + 2e → H2(g)
B. Cu2+(aq) + 2e → Cu(s)
C. 4OH(aq) - 4e → 2H2O(l) + O2(g)
D. SO42(aq) − 2e → SO2(g) + O2(g)

WAEC Shakespeare (The Tempest)

36. Reduction is the process of _____

A. loss of electron
B. loss of hydrogen
C. loss of oxygen
D. addition of electro-negative elements

37. Ethene molecules can be added to one another to form a long chain compound called a _____

A. Dimer
B. Monomer
C. Polymer
D. Trimmer

38. Which of the following compounds determines the octane rating of petrol?

A. 1, 2, 3 - trimethyl Pentane
B. 2, 3, 5 - trimethyl Octane
C. 2, 3, 5 - trimethyl Pentane
D. 2, 2, 4 - trimethyl Pentane

39. Which type of reaction is illustrated by the following equation? C12H26 → 5C2H4 + C2H6

A. Addition
B. Cracking
C. Hydrogenation
D. Polymerization

40. The IUPAC name of the following organic compound HOOC – COOH is _____ 

A. Ethane -1, 2- dioc acid
B. Ethanoic acid
C. Oxalic acid
D. Propane -1, 2- dioic acid

WAEC Shakespeare (The Tempest)

41. The enzyme that catalyze the conversion of glucose to ethanol and carbon (IV) oxide is _____

A. diastase
B. maltose
C. ptyalin
D. zymase

42. A colourless hydrocarbon with a sweet smell undergoes substitution reaction. The hydrocarbon is likely to be _____

A. alkanol
B. benzene
C. ester
D. methane

43. Consider the reaction represented by the following equation: C2H4(g) + 3O2(g) → 2CO2(g) + 2H2O(g). How many moles of ethane would be burnt to produce 0.1mol of water?

A. 0.05 mole
B. 0.10 mole
C. 0.20 mole
D. 2.00 mole

44. The liquid hydrocarbon likely to be found in the fraction of crude oil used for domestic cooking is _____

A. C3H8
B. C5H12
C. C13H28
D. C20H42

45. Which of the following organic compounds could be represented by the empirical formula CH2O?

A. Ethanal
B. Ethane 
C. Ethanol
D. Ethanoic

WAEC Shakespeare (The Tempest)

46. The production of biogas from the fermentation of waste materials is an example of _____

A. Combustion
B. Incineration
C. Refining
D. Recycling

47. The purity of a solid sample can best be determined by its ___

A. boiling point
B. melting point
C. conductivity
D. solubility

48. Which of the following gases is used to retard the vaporization of the filament in a light bulb?

A. Argon
B. Helium
C. Hydrogen
D. Oxygen

49. The most common process in the extraction of metals from their ore is _____

A. catalysis
B. electrolysis
C. oxidation
D. reduction

50. The oxide from electric power station is _____

A. carbon (IV) oxide
B. copper (ll) oxide
C. nitrogen (IV) oxide
D. sulphur (IV) oxide

• This past questions were extracted from the official WAEC 2015 Chemistry paper 1.

Download Chemistry objective WAEC past questions PDF

• OR SEE WAEC CHEMISTRY THEORY PAPERS

GOOD LUCK.

Did you encounter any issue(s) with the study or download of this WAEC Chemistry objective questions? Let us know in the comments below.