✅ Aims and Objectives of Practicing These Chemistry Questions:

Practicing these JAMB Chemistry questions will help you to:

✅ 1. Understand the Exam Style

The questions reflect the real structure, difficulty, and patterns commonly used by JAMB.

✅ 2. Strengthen Your Speed and Accuracy

JAMB is timed. Practicing many questions helps you think faster and avoid careless mistakes.

✅ 3. Identify Weak Areas

You will discover topics where you need further reading—such as stoichiometry, periodic table, thermodynamics, organic chemistry, etc.

✅ 4. Improve Your Problem-Solving Skills

The questions challenge your ability to interpret data, apply formulas, and analyze reactions correctly.

✅ 5. Boost Your Confidence

The more exposed you are to realistic questions, the less anxious you’ll feel on the actual exam day.

✅ 6. Prepare Strategically for 2026 UTME

By practicing ahead, you gain mastery over key topics JAMB repeats almost every year.

✅ 50 JAMB Chemistry Objective Questions and Answers (2026 Practice Set)

1. Which of the following is a chemical change?

A. Melting wax

B. Dissolving sugar

C. Rusting of iron

D. Breaking glass

✅ Answer: C

2. The atomic number of an element represents the number of—

A. Neutrons

B. Electrons only

C. Protons

D. Protons + Neutrons

✅ Answer: C

3. A mixture of sand and salt can best be separated by—

A. Evaporation

B. Distillation

C. Chromatography

D. Dissolution and filtration

✅ Answer: D

4. Which gas turns acidified dichromate paper green?

A. H₂

B. SO₂

C. CO

D. NH₃

✅ Answer: B

5. The shape of a methane molecule is—

A. Linear

B. Tetrahedral

C. Trigonal planar

D. Octahedral

✅ Answer: B

6. The oxidation number of sulfur in H₂SO₄ is—

A. +6

B. +4

C. –2

D. 0

✅ Answer: A

7. The most electronegative element is—

A. Fluorine

B. Oxygen

C. Chlorine

D. Nitrogen

✅ Answer: A

8. The process of coating iron with zinc is called—

A. Alloying

B. Electroplating

C. Galvanization

D. Tempering

✅ Answer: C

9. Which of the following is a strong electrolyte?

A. Sugar solution

B. Ethanol

C. HCl (aq)

D. Distilled water

✅ Answer: C

10. A catalyst increases the rate of a reaction by—

A. Increasing temperature

B. Increasing activation energy

C. Lowering activation energy

D. Increasing pressure

✅ Answer: C

11. A saturated solution contains—

A. More solute than solvent

B. Solute in maximum amount at that temperature

C. Equal solute and solvent

D. No solute

✅ Answer: B

12. Which of the following is a noble gas?

A. Nitrogen

B. Neon

C. Chlorine

D. Argon

✅ Answer: B

13. The pH of a 0.01 M HCl solution is approximately—

A. 1

B. 2

C. 7

D. 10

✅ Answer: A

14. The gas that causes depletion of the ozone layer is—

A. CO₂

B. SO₂

C. CFCs

D. NO

✅ Answer: C

15. Which of these is an endothermic process?

A. Freezing of water

B. Combustion

C. Photosynthesis

D. Neutralization

✅ Answer: C

16. A base that dissolves in water is called—

A. Alkali

B. Salt

C. Oxide

D. Acid anhydride

✅ Answer: A

17. The number of moles in 22 g of CO₂ is— (Molar mass = 44 g/mol)

A. 0.25 mol

B. 0.5 mol

C. 1 mol

D. 2 mol

✅ Answer: B

18. Which of the following is used as a drying agent?

A. H₂O

B. NH₃

C. P₄O₁₀

D. CO₂

✅ Answer: C

19. The main ore of aluminium is—

A. Haematite

B. Bauxite

C. Galena

D. Cassiterite

✅ Answer: B

20. In the periodic table, ionization energy—

A. Increases down a group

B. Decreases across a period

C. Increases across a period

D. Remains constant

✅ Answer: C

21. Which of these is a covalent compound?

A. NaCl

B. MgO

C. H₂O

D. KBr

✅ Answer: C

22. The molecular mass of ethanol (C₂H₆O) is—

A. 24

B. 34

C. 46

D. 60

✅ Answer: C

23. Temporary hardness of water is removed by—

A. Boiling

B. Filtration

C. Chlorination

D. Distillation

✅ Answer: A

24. The IUPAC name of CH₃–CH₂–CH₃ is—

A. Methane

B. Ethane

C. Propane

D. Butane

✅ Answer: C

25. The energy required to remove an electron from a gaseous atom is—

A. Bond energy

B. Ionization energy

C. Electron affinity

D. Lattice energy

✅ Answer: B

26. Hydrogen is placed in group 1 because it—

A. Has one electron in its outer shell

B. Is a metal

C. Forms acidic hydrides

D. Reacts like noble gases

✅ Answer: A

27. Which hydrocarbon is unsaturated?

A. Ethane

B. Propane

C. Ethene

D. Methane

✅ Answer: C

28. The pH of pure water at 25°C is—

A. 0

B. 1

C. 7

D. 14

✅ Answer: C

29. The law of conservation of mass was proposed by—

A. Avogadro

B. Dalton

C. Lavoisier

D. Boyle

✅ Answer: C

30. The noble gas configuration of sodium ion (Na⁺) is similar to—

A. Ne

B. Ar

C. Kr

D. He

✅ Answer: A

31. The chemical formula of aluminium trioxide is—

A. Al₂O

B. AlO₃

C. Al₂O₃

D. Al₃O₂

✅ Answer: C

32. Coal is formed mainly from—

A. Marine plants

B. Dead animals

C. Prehistoric plants

D. Minerals

✅ Answer: C

33. The colour of phenolphthalein in alkaline solution is—

A. Colourless

B. Pink

C. Red

D. Blue

✅ Answer: B

34. An example of an exothermic reaction is—

A. Dissolution of ammonium nitrate

B. Freezing of water

C. Melting ice

D. Decomposition of limestone

✅ Answer: B

35. The SI unit of pressure is—

A. Watt

B. Pascal

C. Newton

D. Joule

✅ Answer: B

36. The gas used in welding is—

A. Methane

B. Acetylene

C. Nitrogen

D. Hydrogen chloride

✅ Answer: B

37. Which of the following is a chemical property of matter?

A. Shape

B. Color

C. Reactivity

D. Mass

✅ Answer: C

38. The bond in NaCl is mainly—

A. Covalent

B. Ionic

C. Metallic

D. Van der Waals

✅ Answer: B

39. The major component of natural gas is—

A. Ethane

B. Butane

C. Methane

D. Propane

✅ Answer: C

40. The electron configuration of chlorine atom is—

A. 1s²2s²2p⁶3s²3p⁵

B. 1s²2s²2p⁶

C. 1s²2s²2p⁶3s²

D. 1s²2s²2p³

✅ Answer: A

41. Which of the following is amphoteric?

A. Na₂O

B. K₂O

C. ZnO

D. CaO

✅ Answer: C

42. A solution that resists changes in pH is—

A. Salt solution

B. Dilute acid

C. Buffer solution

D. Alkali

✅ Answer: C

43. Which gas is collected by downward displacement of water?

A. HCl

B. Cl₂

C. CO₂

D. H₂

✅ Answer: D

44. Which process is used to separate crude oil into fractions?

A. Filtration

B. Fractional distillation

C. Sedimentation

D. Sublimation

✅ Answer: B

45. Which substance is NOT a renewable energy source?

A. Solar

B. Hydro

C. Wind

D. Fossil fuel

✅ Answer: D

46. The number of atoms in 1 mole of oxygen gas is—

A. 6.02 × 10²³

B. 3.01 × 10²³

C. 1.20 × 10²⁴

D. 6.02 × 10²²

✅ Answer: C

47. A conjugate acid-base pair differs by—

A. Proton

B. Neutron

C. Electron

D. Charge only

✅ Answer: A

48. Which of these is used as an antiseptic?

A. Iodine solution

B. Sodium chloride

C. Methane

D. Sand

✅ Answer: A

49. The hybridization in methane is—

A. sp

B. sp²

C. sp³

D. sp³d

✅ Answer: C

50. The substance that absorbs moisture from the atmosphere is—

A. Hygroscopic

B. Efflorescent

C. Deliquescent

D. Anhydrous

✅ Answer: C

✅ ANOTHER SECTION : 40 JAMB-STYLE QUESTIONS

1. Which of the following best explains the term activation energy?

A. Energy needed to break all bonds

B. Minimum energy required for a reaction to occur

C. Energy released during a reaction

D. Energy stored in reactants

✅ Answer: B

2. The percentage of oxygen in BaO₂ is: (Ba = 137, O = 16)

A. 18.9%

B. 29.2%

C. 36.4%

D. 53.3%

✅ Answer: D

3. Which of the following gases is collected by upward delivery?

A. Methane

B. CO₂

C. H₂S

D. Cl₂

✅ Answer: A

4. An element with atomic number 20 belongs to group—

A. 1

B. 2

C. 3

D. 4

✅ Answer: B

5. The IUPAC name of CH₃–CH₂–CH₂–OH is—

A. Methanol

B. Ethanol

C. Propanol

D. Butanol

✅ Answer: C

6. In an endothermic reaction, the enthalpy change is—

A. Positive

B. Negative

C. Zero

D. Undefined

✅ Answer: A

7. The main constituent of biogas is—

A. Ethane

B. Methane

C. Propane

D. Butane

✅ Answer: B

8. Which of the following is an example of a basic oxide?

A. CO₂

B. SO₃

C. CaO

D. NO₂

✅ Answer: C

9. How many moles are in 11 g of CO₂? (Molar mass = 44 g/mol)

A. 0.25

B. 0.50

C. 0.75

D. 1.00

✅ Answer: A

10. Which salt is prepared by double decomposition?

A. NaCl

B. CaCO₃

C. KNO₃

D. CuSO₄

✅ Answer: B

11. A solution with pH = 3 is—

A. Neutral

B. Weakly acidic

C. Strongly acidic

D. Basic

✅ Answer: C

12. The electron configuration of Mg²⁺ is—

A. 1s²2s²2p⁶

B. 1s²2s²2p⁶3s²

C. 1s²2s²2p⁴

D. 1s²2s²2p³

✅ Answer: A

13. The process of converting oils to margarine is—

A. Polymerization

B. Hydrogenation

C. Hydrolysis

D. Isomerization

✅ Answer: B

14. Which instrument measures pressure of gases?

A. Barometer

B. Hygrometer

C. Manometer

D. Thermometer

✅ Answer: C

15. A catalyst is said to be poisoned when—

A. It increases reaction rate

B. Impurities reduce its activity

C. Temperature is lowered

D. Pressure increases

✅ Answer: B

16. The periodic table is arranged in order of—

A. Atomic mass

B. Neutron number

C. Atomic number

D. Ionic radius

✅ Answer: C

17. Which of these is not a colligative property?

A. Osmotic pressure

B. Vapor pressure lowering

C. Boiling point elevation

D. Density

✅ Answer: D

18. Electrolysis of brine produces—

A. Chlorine, sodium, oxygen

B. Chlorine, hydrogen, sodium hydroxide

C. Sodium, hydrogen, oxygen

D. Hydrogen, oxygen only

✅ Answer: B

19. Temporary hardness in water is due to—

A. Ca(HCO₃)₂

B. CaSO₄

C. MgCl₂

D. Na₂CO₃

✅ Answer: A

20. Which of these hydrocarbons is aromatic?

A. Ethyne

B. Propene

C. Benzene

D. Pentane

✅ Answer: C

21. The oxidation state of nitrogen in HNO₃ is—

A. +1

B. +3

C. +5

D. –3

✅ Answer: C

22. Which of these solids has metallic bonding?

A. Diamond

B. Na

C. NaCl

D. Ice

✅ Answer: B

23. The rate of diffusion of gases depends on—

A. Pressure only

B. Temperature only

C. Volume only

D. Relative molecular mass

✅ Answer: D

24. A substance that absorbs moisture but does not dissolve is—

A. Hygroscopic

B. Deliquescent

C. Efflorescent

D. Anhydrous

✅ Answer: A

25. Which acid is used in lead-acid batteries?

A. H₂SO₄

B. HNO₃

C. HCl

D. CH₃COOH

✅ Answer: A

26. The alkaline earth metals are found in—

A. Group I

B. Group II

C. Group III

D. Group IV

✅ Answer: B

27. An example of a neutralization reaction is—

A. CaCO₃ → CaO + CO₂

B. HCl + NaOH → NaCl + H₂O

C. N₂ + 3H₂ → 2NH₃

D. Fe + O₂ → Fe₂O₃

✅ Answer: B

28. Which gas burns with a pop sound?

A. Oxygen

B. Hydrogen

C. Nitrogen

D. Chlorine

✅ Answer: B

29. The main ore of iron is—

A. Bauxite

B. Haematite

C. Dolomite

D. Galena

✅ Answer: B

30. The functional group in ethanol is—

A. –COOH

B. –OH

C. –CHO

D. –COO–

✅ Answer: B

31. The number of neutrons in ⁴⁰Ca is—

A. 20

B. 22

C. 18

D. 40

✅ Answer: A

32. Which of the following is NOT a greenhouse gas?

A. CO₂

B. CH₄

C. O₃

D. N₂

✅ Answer: D

33. The method used to obtain pure nitrogen from air is—

A. Filtration

B. Fractional distillation

C. Sedimentation

D. Diffusion

✅ Answer: B

34. The term efflorescence means—

A. Absorbing water

B. Losing water of crystallization

C. Becoming a liquid

D. Forming an acid

✅ Answer: B

35. The colour of copper(II) sulfate crystals is—

A. Green

B. Blue

C. White

D. Red

✅ Answer: B

36. Which of these is a non-metal?

A. Calcium

B. Sodium

C. Sulfur

D. Zinc

✅ Answer: C

37. An example of a displacement reaction is—

A. NaOH + HCl

B. Cu + 2AgNO₃ → Cu(NO₃)₂ + 2Ag

C. NH₃ + HCl → NH₄Cl

D. C + O₂ → CO₂

✅ Answer: B

38. What is the pH of 0.001 M HCl?

A. 1

B. 2

C. 3

D. 4

✅ Answer: C

39. The highest oxidation state of chlorine is—

A. +3

B. +5

C. +7

D. +1

✅ Answer: C

40. Which gas is responsible for acid rain?

A. O₂

B. SO₂

C. He

D. N₂

✅ Answer: B

41. A substance that speeds up a chemical reaction without being consumed is—

A. A reagent

B. A catalyst

C. A buffer

D. A solute

✅ Answer: B

42. Sodium belongs to which block?

A. s-block

B. p-block

C. d-block

D. f-block

✅ Answer: A

43. The pH of alkaline solutions is—

A. Less than 7

B. Equal to 7

C. Greater than 7

D. Always 14

✅ Answer: C

44. Which of these is an allotrope of carbon?

A. Chrome

B. Diamond

C. Sulfide

D. Nitride

✅ Answer: B

45. The rate of a reaction is increased by—

A. Lower temperature

B. A catalyst

C. Removing reactants

D. Increasing particle size

✅ Answer: B

✅ CONTINUATION — 50 MORE JAMB CHEMISTRY QUESTIONS (Questions 46–90)

46. The gas that turns limewater milky is—

A. CO₂

B. SO₂

C. NH₃

D. H₂

✅ Answer: A

47. Which method is used to separate mixtures of pigments?

A. Filtration

B. Distillation

C. Chromatography

D. Decantation

✅ Answer: C

48. The oxidation number of carbon in CO₂ is—

A. +2

B. +4

C. –2

D. 0

✅ Answer: B

49. Which of the following is a monobasic acid?

A. H₂SO₄

B. H₃PO₄

C. HCl

D. H₂CO₃

✅ Answer: C

50. The major component of air is—

A. Nitrogen

B. Oxygen

C. Carbon dioxide

D. Argon

✅ Answer: A

51. Which gas is used for food preservation?

A. O₂

B. CO₂

C. N₂

D. Cl₂

✅ Answer: C

52. The least reactive metal among the following is—

A. Potassium

B. Sodium

C. Gold

D. Calcium

✅ Answer: C

53. A buffer solution resists changes in—

A. Temperature

B. pH

C. Pressure

D. Concentration

✅ Answer: B

54. The mass of 1 mole of oxygen molecules (O₂) is—

A. 8 g

B. 16 g

C. 32 g

D. 48 g

✅ Answer: C

55. A substance that reacts with acids to form salts is—

A. A base

B. A salt

C. A catalyst

D. A solvent

✅ Answer: A

56. The separation of petrol and kerosene is done by—

A. Simple distillation

B. Crystallization

C. Fractional distillation

D. Filtration

✅ Answer: C

57. Which of these is a greenhouse gas?

A. CO₂

B. N₂

C. He

D. Ar

✅ Answer: A

58. Which salt gives a brick-red flame test?

A. NaCl

B. KCl

C. CaCl₂

D. CuCl₂

✅ Answer: C

59. The process whereby a liquid changes to gas at all temperatures is—

A. Evaporation

B. Boiling

C. Condensation

D. Melting

✅ Answer: A

60. The type of bonding in H₂ is—

A. Metallic

B. Covalent

C. Ionic

D. Dative

✅ Answer: B

61. A substance that can donate a proton is—

A. A base

B. An acid

C. A salt

D. A buffer

✅ Answer: B

62. Which of these oxides is acidic?

A. Na₂O

B. CaO

C. SO₂

D. MgO

✅ Answer: C

63. The catalytic converter in cars removes—

A. CO₂

B. SO₂

C. NO and CO

D. O₂

✅ Answer: C

64. The substance that sublimes is—

A. NaCl

B. NH₄Cl

C. H₂O

D. CuSO₄

✅ Answer: B

65. The relative atomic mass of chlorine is approximately 35.5 because—

A. It is unstable

B. It has isotopes

C. It reacts with sodium

D. Its electrons vary

✅ Answer: B

66. The atomicity of ozone is—

A. 1

B. 2

C. 3

D. 4

✅ Answer: C

67. A solution that contains more solute than it can normally hold is—

A. Dilute

B. Saturated

C. Supersaturated

D. Unsaturated

✅ Answer: C

68. An example of a coordinate covalent bond is found in—

A. CH₄

B. NH₄⁺

C. NaCl

D. H₂O

✅ Answer: B

69. Which gas is least dense?

A. CO₂

B. O₂

C. H₂

D. N₂

✅ Answer: C

70. The process of extracting metals from ores is called—

A. Mining

B. Refining

C. Metallurgy

D. Purification

✅ Answer: C

71. The colour of litmus in acid is—

A. Blue

B. Red

C. Green

D. Purple

✅ Answer: B

72. The hydrocarbon with formula C₅H₁₂ is—

A. Pentane

B. Butane

C. Hexane

D. Propane

✅ Answer: A

73. Which gas supports combustion?

A. CO₂

B. He

C. O₂

D. NO₂

✅ Answer: C

74. The electron configuration of phosphorus (Z = 15) is—

A. 1s²2s²2p⁶3s²3p³

B. 1s²2s²2p⁶3s²3p⁴

C. 1s²2s²2p⁶3s¹

D. 1s²2s²2p⁵

✅ Answer: A

75. The fractional distillation of air gives—

A. CO₂ and CO

B. H₂ and N₂

C. O₂ and N₂

D. SO₂ and O₃

✅ Answer: C

76. Which of these is a reducing agent?

A. O₂

B. Cl₂

C. H₂

D. He

✅ Answer: C

77. The main product of fermentation is—

A. Methanol

B. Ethanol

C. Propanol

D. Butanol

✅ Answer: B

78. Which salt is formed when HCl reacts with NaOH?

A. Na₂SO₄

B. NaCl

C. NaNO₃

D. KCl

✅ Answer: B

79. A radioactive isotope used for dating fossils is—

A. U-238

B. C-14

C. I-131

D. Co-60

✅ Answer: B

80. A solution with pH = 7 is—

A. Neutral

B. Acidic

C. Basic

D. Concentrated

✅ Answer: A

81. The colour of bromine is—

A. Green

B. Red-brown

C. Yellow

D. Colourless

✅ Answer: B

82. A strong acid is one that—

A. Reacts slowly

B. Ionizes completely

C. Ionizes partially

D. Is highly concentrated

✅ Answer: B

83. Which of these is an endothermic change?

A. Freezing water

B. Burning fuel

C. Melting ice

D. Condensation

✅ Answer: C

84. The instrument for measuring temperature is—

A. Manometer

B. Hygrometer

C. Thermometer

D. Barometer

✅ Answer: C

85. Which oxide is amphoteric?

A. Na₂O

B. MgO

C. ZnO

D. CO₂

✅ Answer: C

86. A solution that turns red litmus paper blue is—

A. Acid

B. Base

C. Salt

D. Buffer

✅ Answer: B

87. The main raw material for glass making is—

A. Limestone

B. Sand

C. Clay

D. Sodium

✅ Answer: B

88. Which of these is a halogen?

A. Neon

B. Argon

C. Fluorine

D. Sodium

✅ Answer: C

89. The energy released when one mole of gaseous ions forms a solid ionic crystal is—

A. Ionization energy

B. Electron affinity

C. Lattice energy

D. Bond energy

✅ Answer: C

90. Which compound is used to soften hard water?

A. Sodium chloride

B. Sodium carbonate

C. Sodium nitrate

D. Sodium hydroxide

✅ Answer: B

✅ TOPIC-BY-TOPIC SOLVED CHEMISTRY CALCULATIONS (Most Tested in JAMB)

These are the exact types of calculation questions JAMB repeats every year.

✅ 1. Mole Concept & Stoichiometry

Example 1:

How many moles are in 8.8 g of CO₂?

(Molar mass of CO₂ = 44 g/mol)✅ Solution:

Moles = Mass ÷ Molar Mass

= 8.8 ÷ 44

= 0.2 mol✅ Final Answer: 0.2 mol

Example 2:

How many molecules are in 0.5 moles of a substance?✅ Solution:

Number of molecules = moles × Avogadro’s number

= 0.5 × 6.02 × 10²³

= 3.01 × 10²³ molecules✅ Final Answer: 3.01 × 10²³

✅ 2. Gas Laws (Boyle, Charles, Combined Gas Law)

Example 3: Boyle’s Law

A gas has a volume of 600 cm³ at 300 kPa.

What is its volume at 200 kPa?✅ Solution:

P₁V₁ = P₂V₂

300 × 600 = 200 × V₂

V₂ = (300 × 600) ÷ 200

= 900 cm³✅ Final Answer: 900 cm³

Example 4: Charles’ Law

A gas occupies 200 cm³ at 27°C (300 K).

What is its volume at 57°C (330 K)?✅ Solution:

V₁/T₁ = V₂/T₂

200/300 = V₂/330

V₂ = (200 × 330) ÷ 300

= 220 cm³✅ Final Answer: 220 cm³

✅ 3. Concentration & Titration

Example 5: Molarity

Calculate the concentration when 4.9 g of H₂SO₄ is dissolved to make 1 dm³ solution.

(Molar mass = 98 g/mol)✅ Solution:

Moles = 4.9 / 98 = 0.05 mol

Concentration = moles / volume = 0.05 / 1

= 0.05 mol/dm³✅ Final Answer: 0.05 M

Example 6: Titration Calculation

25 cm³ of NaOH was neutralized by 20 cm³ of 0.1 M HCl.

Find the concentration of NaOH.

Reaction: NaOH + HCl → NaCl + H₂O✅ Solution:

M₁V₁ = M₂V₂

M(NaOH) × 25 = 0.1 × 20

M(NaOH) = (0.1 × 20) ÷ 25

= 0.08 M✅ Final Answer: 0.08 mol/dm³

✅ 4. Empirical & Molecular Formula

Example 7:

A compound contains 75% carbon, 25% hydrogen.

Find its empirical formula.✅ Solution:

Carbon: 75 ÷ 12 = 6.25

Hydrogen: 25 ÷ 1 = 25Divide both by the smallest (6.25):

C = 6.25/6.25 = 1

H = 25/6.25 = 4✅ Empirical formula = CH₄

✅ 5. Heat of Reaction (Enthalpy)

Example 8:

Calculate ΔH if:

Mass of water = 100 g

Temperature change = 20°C to 35°C

Specific heat capacity = 4.2 J/g°C✅ Solution:

Q = mcΔT

Q = 100 × 4.2 × (35 – 20)

Q = 100 × 4.2 × 15

Q = 6300 J✅ Final Answer: 6.3 kJ

✅ 6. Radioactivity Calculations

Example 9: Half-Life

A radioactive material has a half-life of 3 days.

If you start with 80 g, how much remains after 9 days?✅ Solution:

Number of half-lives = 9/3 = 3

Remaining = 80 × (1/2)³

= 80 × 1/8

= 10 g✅ Final Answer: 10 g

✅ 7. Electrolysis Calculations

Example 10: Electrochemical equivalent

Charge passed = 9650 C

E.C.E of Ag = 0.001118 g/C

Calculate mass deposited.✅ Solution:

Mass = ZIt

Mass = 0.001118 × 9650

= 10.79 g✅ Final Answer: 10.8 g

✅ These are the most tested calculations in JAMB Chemistry.

If you master these styles, you're already ahead of 80% of this course. 

✅ SECTION A — JAMB CHEMISTRY MOCK EXAM (40 QUESTIONS + ANSWERS)

Standard: 2026 JAMB Format

Duration if you attempt it yourself: 45 minutes

1. Which of the following is a chemical change?

A. Melting of ice

B. Breaking of glass

C. Rusting of iron

D. Filtration of sand✅ Answer: C

2. The atomic number of an element is equal to its number of:

A. Electrons only

B. Protons only

C. Neutrons

D. Protons + electrons✅ Answer: B

3. A gas occupies 400 cm³ at 300 K. What is its volume at 600 K?

A. 200 cm³

B. 300 cm³

C. 600 cm³

D. 800 cm³✅ Answer: D

4. Which of these is not an alkali?

A. NaOH

B. Ca(OH)₂

C. NH₄OH

D. CuO✅ Answer: D

5. How many neutrons are in ³⁷Cl (atomic number = 17)?

A. 17

B. 20

C. 37

D. 54✅ Answer: B

6. Which bond is formed between calcium and chlorine?

A. Covalent

B. Metallic

C. Ionic

D. Coordinate✅ Answer: C

7. The oxidation number of sulphur in H₂SO₄ is:

A. +2

B. +4

C. +6

D. −2✅ Answer: C

8. Which of the following gases turns limewater milky?

A. CO

B. CO₂

C. SO₂

D. NH₃✅ Answer: B

9. What is the pH of 1 × 10⁻⁴ M HCl?

A. 4

B. 10

C. 14

D. 2✅ Answer: A

10. What is the IUPAC name of CH₃CH₂CHO?

A. Propanal

B. Propanone

C. Propene

D. Propanol✅ Answer: A

Questions 11–40 + Answers

11. Which of the following processes is endothermic?

A. Freezing

B. Condensation

C. Melting

D. Liquefaction✅ Answer: C

12. The separation technique used to obtain ethanol from water is:

A. Filtration

B. Evaporation

C. Fractional distillation

D. Crystallization✅ Answer: C

13. Which gas will relight a glowing splint?

A. Nitrogen

B. Hydrogen

C. Oxygen

D. Carbon dioxide✅ Answer: C

14. What is the molar volume of a gas at STP?

A. 12 dm³

B. 18 dm³

C. 22.4 dm³

D. 32 dm³✅ Answer: C

**15. In the reaction:

2Na + 2H₂O → 2NaOH + H₂**,

the oxidizing agent is:

A. Water

B. Sodium

C. NaOH

D. Hydrogen✅ Answer: A

16. Which instrument is used to measure relative humidity?

A. Hygrometer

B. Thermometer

C. Barometer

D. Hydrometer✅ Answer: A

17. A solution that resists change in pH is called:

A. Buffer

B. Indicator

C. Solvent

D. Electrolyte✅ Answer: A

18. Which element has the highest electronegativity?

A. Sodium

B. Fluorine

C. Oxygen

D. Chlorine✅ Answer: B

19. The major product of the reaction between ethene and hydrogen is:

A. Ethanol

B. Ethyne

C. Ethane

D. Propane✅ Answer: C

20. Which ore is used in the extraction of iron?

A. Bauxite

B. Haematite

C. Galena

D. Cassiterite✅ Answer: B

21. The electron configuration of potassium is:

A. 2, 8, 8

B. 2, 8, 1

C. 2, 8, 8, 1

D. 2, 6, 7✅ Answer: C

**22. Which type of reaction is:

AB → A + B?**

A. Combination

B. Displacement

C. Decomposition

D. Redox✅ Answer: C

23. The functional group of alcohols is:

A. –COOH

B. –OH

C. –CHO

D. –NH₂✅ Answer: B

24. An atom that gains an electron becomes:

A. Cation

B. Proton

C. Neutron

D. Anion✅ Answer: D

25. Air is a mixture because:

A. It contains nitrogen alone

B. Its components can vary

C. It has a fixed composition

D. It is a compound✅ Answer: B

26. Another name for trioxonitrate(V) acid is:

A. Nitrous acid

B. Nitric acid

C. Sulphuric acid

D. Hydrochloric acid✅ Answer: B

27. Which of the following is NOT a greenhouse gas?

A. CO₂

B. CH₄

C. O₃

D. N₂✅ Answer: D

28. The major property of transition metals is:

A. They are colourless

B. They form coloured ions

C. They are very reactive

D. They have low melting points✅ Answer: B

29. Which of these is a saturated hydrocarbon?

A. Alkyne

B. Alkene

C. Alkane

D. Benzene✅ Answer: C

30. Which law explains the relationship between pressure and volume?

A. Boyle’s law

B. Charles’ law

C. Dalton’s law

D. Graham’s law✅ Answer: A

31. The pH of a neutral solution is:

A. 0

B. 5

C. 7

D. 14✅ Answer: C

32. The salt formed from nitric acid and potassium hydroxide is:

A. Sodium nitrate

B. Potassium nitrate

C. Potassium sulphate

D. Ammonium nitrate✅ Answer: B

33. A catalyst works by:

A. Increasing activation energy

B. Lowering activation energy

C. Increasing pressure

D. Increasing temperature✅ Answer: B

34. The gas used in balloons is:

A. Oxygen

B. Helium

C. Nitrogen

D. Neon✅ Answer: B

35. What is the oxidation state of carbon in CO₂?

A. +2

B. –4

C. +4

D. 0✅ Answer: C

36. The major constituent of natural gas is:

A. Ethane

B. Propane

C. Methane

D. Butane✅ Answer: C

37. Hardness in water is caused by:

A. NaCl

B. Ca(HCO₃)₂

C. KOH

D. H₂✅ Answer: B

38. Which of these substances is used as a drying agent?

A. CaCl₂

B. KNO₃

C. NaCl

D. H₂SO₄(aq)✅ Answer: A

39. The monomer of polythene is:

A. Ethyne

B. Ethene

C. Benzene

D. Propene✅ Answer: B

40. Which radiation has the highest penetrating power?

A. Alpha

B. Beta

C. Gamma

D. Proton✅ Answer: C

✅ 50 LIKELY CHEMISTRY QUESTIONS & ANSWERS

1. Which of the following is a noble gas?

A. Neon

B. Nitrogen

C. Oxygen

D. Helium oxide✅ Answer: A

2. The separation of a mixture of salt and sand is achieved by:

A. Filtration → Evaporation

B. Distillation → Filtration

C. Crystallization → Filtration

D. Evaporation → Chromatography✅ Answer: A

3. The number of atoms in 1 mole of oxygen gas is:

A. 6.02 × 10²³

B. 1.204 × 10²⁴

C. 3.01 × 10²³

D. 6.02 × 10²⁴✅ Answer: B(O₂ has 2 atoms → 2 × 6.02 × 10²³)

4. Which of the following is a chemical change?

A. Dissolution of sugar

B. Melting of ice

C. Rusting of iron

D. Breaking of glass✅ Answer: C

5. The process of converting gas to solid is:

A. Sublimation

B. Deposition

C. Condensation

D. Freezing✅ Answer: B

6. The oxidation state of chlorine in NaClO₃ is:

A. +1

B. –1

C. +5

D. +3✅ Answer: C

7. Which of the following is used to soften water?

A. Sodium chloride

B. Sodium carbonate

C. Potassium nitrate

D. Lead (II) nitrate✅ Answer: B

8. A solution with pH 2 is:

A. Neutral

B. Slightly acidic

C. Strongly acidic

D. Strongly basic✅ Answer: C

9. The electron configuration of magnesium is:

A. 2, 8

B. 2, 8, 2

C. 2, 6, 8

D. 2, 6, 10✅ Answer: B

10. Which of these processes is exothermic?

A. Melting

B. Vaporization

C. Freezing

D. Evaporation✅ Answer: C

11. A standard solution is:

A. Any solution

B. A saturated solution

C. A solution of known concentration

D. A solution that conducts electricity✅ Answer: C

12. In electrolysis, oxidation occurs at the:

A. Cathode

B. Anode

C. Both electrodes

D. Salt bridge✅ Answer: B

13. The major product of complete combustion of methane is:

A. CO

B. CO₂ and H₂O

C. CH₄O

D. C and H₂O✅ Answer: B

14. Which of the following is NOT a strong acid?

A. H₂SO₄

B. HNO₃

C. HCl

D. CH₃COOH✅ Answer: D

15. The functional group in alkanols is:

A. –COOH

B. –CHO

C. –OH

D. –NH₂✅ Answer: C

16. The formula of copper(II) trioxocarbonate(IV) is:

A. CuCO₃

B. Cu₂CO₃

C. Cu(CO₃)₂

D. CuO₂✅ Answer: A

17. Which gas is collected over water using downward delivery?

A. Hydrogen

B. Ammonia

C. Chlorine

D. Carbon dioxide✅ Answer: C

18. A catalyst increases reaction rate by:

A. Increasing temperature

B. Increasing pressure

C. Lowering activation energy

D. Increasing particle size✅ Answer: C

19. The colour of Fe²⁺ solution is:

A. Green

B. Blue

C. Yellow

D. Brown✅ Answer: A

20. The term “allotropy” refers to elements that:

A. Have the same mass

B. Share electrons

C. Exist in different physical forms

D. Dissolve in water✅ Answer: C

21. Which of the following is used in bleaching?

A. CO₂

B. SO₂

C. N₂

D. He✅ Answer: B

22. The IUPAC name of CH₃–CH₂–O–CH₃ is:

A. Methoxyethane

B. Ethoxymethane

C. Dimethyl ether

D. Ethanol✅ Answer: A

23. A gas effuses through a fine hole. This explains:

A. Boyle’s law

B. Charles’ law

C. Graham’s law

D. Dalton’s law✅ Answer: C

24. The type of bond in ammonium ion (NH₄⁺) is:

A. Metallic

B. Ionic

C. Coordinate covalent

D. Non-polar✅ Answer: C

25. Which of these is a secondary alcohol?

A. Propan-1-ol

B. Ethanol

C. Propan-2-ol

D. Methanol✅ Answer: C

26. The first organic compound synthesized in the laboratory was:

A. Methanol

B. Urea

C. Ethanol

D. Acetic acid✅ Answer: B

27. The relative atomic mass of chlorine is 35.5. This shows:

A. It has equal isotopes

B. It has no isotopes

C. It exists as isotopes of different masses

D. It is radioactive✅ Answer: C

28. Which of these is NOT a property of acids?

A. Turn blue litmus red

B. Taste sour

C. Form salts with bases

D. Feel slippery✅ Answer: D (Bases feel slippery)

29. The shape of methane (CH₄) is:

A. Linear

B. Trigonal planar

C. Tetrahedral

D. Bent✅ Answer: C

30. The law of definite proportion was given by:

A. Avogadro

B. Proust

C. Dalton

D. Boyle✅ Answer: B

31. Which of the following has the highest boiling point?

A. Ethane

B. Ethanol

C. Propane

D. Methane✅ Answer: B (H-bonding)

32. The main constituent of limestone is:

A. CaCO₃

B. CaO

C. Ca(OH)₂

D. CaCl₂✅ Answer: A

33. The colour of phenolphthalein in a base is:

A. Colourless

B. Blue

C. Pink

D. Red✅ Answer: C

34. The major component of air is:

A. Oxygen

B. Argon

C. Nitrogen

D. CO₂✅ Answer: C

35. Which of these gases forms a white precipitate with HCl?

A. NH₃

B. SO₂

C. H₂S

D. CO₂✅ Answer: A

36. The pH of a neutral buffer is:

A. 4

B. 7

C. 10

D. 14✅ Answer: B

37. Which of these is used as an antacid?

A. NaCl

B. Mg(OH)₂

C. H₂SO₄

D. CuSO₄✅ Answer: B

38. The alkane with the formula C₅H₁₂ is:

A. Pentane

B. Butane

C. Propane

D. Ethane✅ Answer: A

39. The main impurity removed during water treatment is:

A. Copper

B. Microorganisms

C. Nitrogen

D. Helium✅ Answer: B

40. The gas that burns with a blue flame is:

A. CO

B. H₂

C. CH₄

D. SO₂✅ Answer: C

41. An electrolyte is a substance that:

A. Boils at a low temperature

B. Conducts electricity when molten or in solution

C. Has a high melting point

D. Is insoluble✅ Answer: B

42. During redox reactions, reduction is:

A. Loss of electrons

B. Gain of electrons

C. Loss of protons

D. Gain of energy✅ Answer: B

43. What is the colour of copper(II) ion in aqueous solution?

A. Brown

B. Green

C. Blue

D. Yellow✅ Answer: C

44. The polymer formed from chloroethene is:

A. PVC

B. Nylon

C. Terylene

D. Bakelite✅ Answer: A

45. Which of the following dissolves in water to form a base?

A. CO₂

B. Cl₂

C. Na₂O

D. SO₂✅ Answer: C

46. The hybridization of carbon in ethyne (C₂H₂) is:

A. sp³

B. sp²

C. sp

D. sp³d✅ Answer: C

47. The type of crystalline solid formed by diamond is:

A. Ionic

B. Covalent

C. Metallic

D. Molecular✅ Answer: B

48. An amphoteric oxide reacts with:

A. Only bases

B. Only acids

C. Both acids and bases

D. Neither acids nor bases✅ Answer: C

49. The solubility of gases in water increases with:

A. Decrease in pressure

B. Increase in temperature

C. Increase in pressure

D. Increase in volume✅ Answer: C

50. The major product of fermentation of glucose is:

A. Ethanoic acid

B. Ethanol

C. Propanol

D. Methanol✅ Answer: B

FULL CHEMISTRY SUMMARY FOR ALL JAMB TOPICS (2026 UPDATE)

This is a clean, complete, and exam-focused summary covering everything JAMB tests.

Read this carefully and you will answer at least 80% of Chemistry questions correctly.

✅ 1. Basic Concepts in Chemistry

Chemistry deals with the study of matter, its composition, properties and the changes it undergoes.

Key Ideas:

• Matter exists in solid, liquid, gas phases.
• Physical changes do NOT form new substances.
• Chemical changes form NEW substances.

Laws of Chemical Combination

✅ Law of conservation of mass – mass is neither created nor destroyed.

✅ Law of definite proportions – a compound always contains elements in fixed ratios.

✅ Law of multiple proportions – elements can combine in different ratios to form different compounds.

✅ 2. Atomic Structure

• Atoms contain protons (+), electrons (−), and neutrons (0).
• Atomic number (Z) = number of protons
• Mass number (A) = protons + neutrons
• Isotopes: same atomic number, different mass number.

Electron Configuration Examples:

• Na (11): 2, 8, 1
• Mg (12): 2, 8, 2

✅ 3. The Periodic Table

Elements are arranged in increasing atomic number.

Trends Across the Period:

• Ionization energy ↑
• Electronegativity ↑
• Atomic radius ↓
• Metallic character ↓

Trends Down the Group:

• Atomic size ↑
• Metallic character ↑
• Ionization energy ↓

Transition metals form colored ions, act as catalysts, and have variable oxidation states.

✅ 4. Chemical Bonding

Types of Bonding:

✅ Ionic: transfer of electrons (e.g., NaCl)

✅ Covalent: sharing of electrons (e.g., H₂, CO₂)

✅ Dative/coordinate: both electrons from one atom

✅ Metallic: sea of electrons in metals

Molecular Shapes (VSEPR):

• CH₄ → tetrahedral
• NH₃ → pyramidal
• H₂O → bent
• CO₂ → linear

✅ 5. Stoichiometry & Mole Concept

Mole = 6.02 × 10²³ particles

Molar volume = 22.4 dm³ at STP

Key Formulas:

• Moles = mass / molar mass
• Gas law: PV = nRT
• Concentration = moles / volume

✅ 6. States of Matter & Gas Laws

Boyle’s Law:

P₁V₁ = P₂V₂

Charles’ Law:

V₁/T₁ = V₂/T₂

Ideal Gas Equation:

PV = nRTEffusion of gases follows Graham’s law.

✅ 7. Solutions, Solubility & Concentration

• Solubility = amount that dissolves in 100 g of solvent.
• Saturated solution holds maximum solute.
• Solubility of solids increases with ↑ temperature.
• Solubility of gases increases with ↑ pressure (Henry’s law).

✅ 8. Acids, Bases & Salts

Acids: release H⁺

Bases: release OH⁻

Salts: reaction of acid and base

pH scale:

• 0–6: acidic
• 7: neutral
• 8–14: basic

Indicators:

• Litmus: red in acid, blue in base
• Phenolphthalein: pink in base
• Methyl orange: red in acid

✅ 9. Chemical Kinetics

Rate increases with:

• Higher temperature
• Larger surface area
• Higher concentration
• Presence of catalyst
• Higher pressure (for gases)

Catalysts lower activation energy.

✅ 10. Chemical Equilibrium

Reversible reactions reach equilibrium when forward = backward rates.

Le Chatelier’s Principle:

A system shifts to oppose change.

• ↑ temperature → favors endothermic
• ↑ pressure → favors fewer moles of gas
• ↑ concentration → shifts away from added species

✅ 11. Redox Reactions

• Oxidation: loss of electrons
• Reduction: gain of electrons

Oxidizing agent is reduced.

Reducing agent is oxidized.

✅ 12. Electrochemistry

Electrolysis: decomposition using electricity

• Oxidation occurs at anode (+)
• Reduction occurs at cathode (−)

Examples:

Electrolysis of brine → H₂, Cl₂, NaOH

Electrochemical Cells:

• Anode = oxidation
• Cathode = reduction

✅ 13. Thermochemistry

• Exothermic: releases heat (ΔH negative)
• Endothermic: absorbs heat (ΔH positive)

Q = mcΔT

✅ 14. Organic Chemistry

Hydrocarbons:

Alkanes (CnH₂n+₂) — saturated

Alkenes (CnH₂n) — unsaturated

Alkynes (CnH₂n−₂)

Functional Groups:

• Alcohols: –OH
• Aldehydes: –CHO
• Ketones: –CO–
• Acids: –COOH
• Amines: –NH₂
• Esters: –COO–

Reactions:

• Addition: alkenes
• Substitution: alkanes
• Esterification: acid + alcohol

✅ 15. Polymers

Examples:

• Ethene → polythene
• Chloroethene → PVC
• Amino acids → proteins
• Glucose → starch

✅ 16. Metals & Their Compounds

Iron extraction: blast furnace

Aluminum extraction: electrolysis of bauxite

Copper extraction: roasting/smeltingCorrosion of iron = rusting (oxidation)

✅ 17. Water

• Hardness caused by Ca²⁺ or Mg²⁺ ions
• Temporary hardness removed by boiling
• Permanent hardness removed by washing soda

Water treatment removes:

• Suspended particles
• Microorganisms
• Dissolved gases

✅ 18. Environmental Chemistry

Major pollutants: CO, SO₂, NO, CO₂, CH₄

Effects:

• Acid rain
• Global warming
• Ozone depletion
• Smog

✅ 19. Nuclear Chemistry

Types of radiation:

• Alpha (low penetration)
• Beta (medium)
• Gamma (high)

Half-life = time for half the nuclei to decay.

✅  FULL JAMB MOCK EXAM (PHYSICS + CHEMISTRY + BIOLOGY)

✅ PHYSICS — 40 JAMB MOCK QUESTIONS

1. The slope of a distance–time graph represents

A. velocity

B. acceleration

C. displacement

D. force

✅ Answer: A

2. A car accelerates from rest at 2 m/s² for 10 s. Its final velocity is

A. 5 m/s

B. 10 m/s

C. 20 m/s

D. 40 m/s

✅ Answer: C

3. Which of the following is a vector quantity?

A. Speed

B. Temperature

C. Mass

D. Momentum

✅ Answer: D

4. A ball of weight 10 N is lifted 5 m. The work done is

A. 2 J

B. 15 J

C. 50 J

D. 100 J

✅ Answer: C

5. The instrument used to measure relative humidity is

A. Hydrometer

B. Hygrometer

C. Barometer

D. Manometer

✅ Answer: B

6. The rate of heat flow through a metal depends on the following EXCEPT

A. thermal conductivity

B. temperature difference

C. length of the rod

D. color of the rod

✅ Answer: D

7. A body floats in water because

A. its mass is small

B. its weight is zero

C. upthrust equals weight

D. density of water is less

✅ Answer: C

8. Sound cannot travel through

A. solids

B. liquids

C. gases

D. vacuum

✅ Answer: D

9. The unit of electrical resistance is

A. watt

B. volt

C. coulomb

D. ohm

✅ Answer: D

10. A transformer works on the principle of

A. conduction

B. radiation

C. mutual induction

D. resonance

✅ Answer: C

11. A convex lens produces a virtual image when the object is placed

A. at 2F

B. at F

C. between F and the lens

D. beyond 2F

✅ Answer: C

12. Which color has the shortest wavelength?

A. Red

B. Yellow

C. Blue

D. Violet

✅ Answer: D

13. A battery is an example of

A. mechanical energy source

B. chemical energy source

C. nuclear energy source

D. light energy source

✅ Answer: B

14. Which wave is mechanical?

A. X-ray

B. Radio wave

C. Sound wave

D. Infrared

✅ Answer: C

15. The device used to convert AC to DC is

A. transformer

B. diode

C. capacitor

D. transistor

✅ Answer: B

16. Ohm’s law states that

A. V ∝ 1/R

B. V ∝ I

C. V ∝ R

D. V = IR²

✅ Answer: B

17. The speed of light in vacuum is

A. 3 × 10² m/s

B. 3 × 10⁴ m/s

C. 3 × 10⁵ m/s

D. 3 × 10⁸ m/s

✅ Answer: D

18. The focal length of a plane mirror is

A. +10 cm

B. 0 cm

C. –5 cm

D. ∞

✅ Answer: D

19. In an electromagnetic wave, the electric and magnetic fields are

A. parallel

B. perpendicular

C. opposite

D. random

✅ Answer: B

20. A fuse protects electrical appliances by

A. increasing current

B. reducing voltage

C. melting when current is high

D. generating heat

✅ Answer: C

✅ Momentum, Machines & Energy

21. Momentum is defined as

A. force per unit time

B. mass × acceleration

C. mass × velocity

D. energy × time

✅ Answer: C

22. Efficiency of a machine is

A. input/output

B. output/input × 100

C.力 × 力

D. 1/power

✅ Answer: B

23. A body in uniform motion has

A. zero velocity

B. constant velocity

C. increasing velocity

D. decreasing velocity

✅ Answer: B

24. The energy possessed due to motion is

A. potential energy

B. heat energy

C. kinetic energy

D. chemical energy

✅ Answer: C

25. A 40 W bulb works for 5 hours. The energy consumed is

A. 200 J

B. 200 Wh

C. 200 kWh

D. 5 kJ

✅ Answer: B

✅ Heat, Waves & Electricity

26. Heat transfer by convection occurs mostly in

A. solids

B. liquids

C. gases

D. both B and C

✅ Answer: D

27. The pitch of sound depends on

A. amplitude

B. frequency

C. wavelength

D. velocity

✅ Answer: B

28. A rheostat is used to

A. increase temperature

B. vary resistance

C. store charge

D. measure voltage

✅ Answer: B

29. A material that allows charges to flow freely is

A. conductor

B. insulator

C. semiconductor

D. diode

✅ Answer: A

30. A ray of light incident at 30° on a plane mirror is reflected at

A. 15°

B. 30°

C. 45°

D. 60°

✅ Answer: B

✅ Modern Physics

31. The nucleus of an atom contains

A. electrons only

B. protons only

C. protons and neutrons

D. neutrons only

✅ Answer: C

32. The charge of an electron is

A. +1.6 × 10⁻¹⁹ C

B. –1.6 × 10⁻¹⁹ C

C. +1 C

D. –1 C

✅ Answer: B

33. Radioactivity is a _______ process.

A. chemical

B. physical

C. biological

D. nuclear

✅ Answer: D

34. Beta particles are

A. helium nuclei

B. high-speed electrons

C. photons

D. protons

✅ Answer: B

35. The device for detecting radiation is

A. barometer

B. gyroscope

C. Geiger-Müller tube

D. hygrometer

✅ Answer: C

✅ General Physics

36. A scalar quantity has

A. magnitude only

B. direction only

C. both magnitude and direction

D. no magnitude

✅ Answer: A

37. The density of a material is

A. mass × volume

B. mass + volume

C. mass / volume

D. volume / mass

✅ Answer: C

38. The S.I unit of pressure is

A. pascal

B. joule

C. volt

D. watt

✅ Answer: A

39. Weight is

A. mass × acceleration due to gravity

B. mass/volume

C. force × distance

D. energy/mass

✅ Answer: A

40. The force that opposes motion between two surfaces is

A. tension

B. friction

C. upthrust

D. thrust

✅ Answer: B