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Instruction
JAMB Chemistry 2002
JAMB (UTME)
Chemistry
2002
Q8801.In the diagram above, the gas evolved is
ANH₃
BNO₂
CN₂O
DO₂
Correct Answer: A
The setup shows the heating of a mixture of NH₄Cl and Ca(OH)₂ to produce ammonia gas.
JAMB (UTME)
Chemistry
2002
Q8802.The IUPAC name for the compound CH₃CH₂CH₂Br is
A1-bromopropane
B2-bromopropane
C3-bromopropane
D1-bromobutane
Correct Answer: A
The compound is a 3-carbon chain with a bromine at position 1. It is 1-bromopropane.
JAMB (UTME)
Chemistry
2002
Q8803.Carbohydrates are compounds containing carbon, hydrogen and oxygen in the ratio
A3:1:1
B2:1:1
C1:2:1
D1:1:1
Correct Answer: C
The general formula for carbohydrates is Cₙ(H₂O)ₘ, so the ratio of C:H:O is 1:2:1.
JAMB (UTME)
Chemistry
2002
Q8804.How many isomers does pentane have?
A6
B5
C4
D3
Correct Answer: D
Pentane (C₅H₁₂) has three isomers: n-pentane, isopentane (2-methylbutane), and neopentane (2,2-dimethylpropane).
JAMB (UTME)
Chemistry
2002
Q8805.The leachate of a certain plant ash is used in local soap making because it contains
Asodium chloride
Bsodium hydroxide
Cpotassium hydroxide
Dcalcium hydroxide
Correct Answer: A
Plant ash contains potassium carbonate (potash), which is an alkali used in local soap making. (The provided answer E is a typo; the correct answer is C, potassium hydroxide, when dissolved in water).
JAMB (UTME)
Chemistry
2002
Q8806.The formula for ethyl butanoate is
AC₂H₅COOC₂H₅
BC₂H₅COOC₄H₉
CC₄H₉COOC₂H₅
DC₂H₅COOC₄H₉
Correct Answer: C
Ethyl butanoate is formed from ethanol (C₂H₅OH) and butanoic acid (C₄H₉COOH). The formula is C₄H₉COOC₂H₅.
JAMB (UTME)
Chemistry
2002
Q8807.The type of reaction that is peculiar to benzene is
Aaddition
Bhydrolysis
Cpolymerization
Dsubstitution
Correct Answer: D
Benzene undergoes electrophilic substitution reactions (e.g., nitration, halogenation) rather than addition reactions.
JAMB (UTME)
Chemistry
2002
Q8808.Ethanol reacts with excess acidified K₂Cr₂O₇ to give
Aethanedioic acid
Bethanal
Cethyl ethanoate
Dethanoic acid
Correct Answer: D
Excess acidified K₂Cr₂O₇ is a strong oxidizing agent that oxidizes ethanol to ethanoic acid.
JAMB (UTME)
Chemistry
2002
Q8809.A compound contains 40.0% carbon, 6.7% hydrogen and 53.3% oxygen. If the molar mass of the compound is 180, find the molecular formula.
ACH₂O
BC₃H₆O₃
CC₆H₁₂O₆
DC₆H₁₂O₆
Correct Answer: C
Moles ratio: C = 40/12 = 3.33, H = 6.7/1 = 6.7, O = 53.3/16 = 3.33. Ratio = 1:2:1. Empirical formula = CH₂O (M=30). n = 180/30 = 6. Molecular formula = C₆H₁₂O₆.
JAMB (UTME)
Chemistry
2002
Q8810.The process by which atoms are rearranged into different molecular structures in the petroleum refining process is referred to as
Acatalytic cracking
Bhydrocracking
Cpolymerization
Dreforming
Correct Answer: D
Reforming is the process of rearranging hydrocarbon molecules to improve their quality (e.g., converting straight-chain alkanes to branched-chain or aromatic compounds).
JAMB (UTME)
Chemistry
2002
Q8811.Which of the following is found in cotton?
AStarch
BCellulose
CFat
DOil
Correct Answer: B
Cotton is almost pure cellulose.
JAMB (UTME)
Chemistry
2002
Q8812.The principal constituent of natural gas is
Amethane
Bethane
Cpropane
Dbutane
Correct Answer: A
Natural gas is composed primarily of methane (CH₄).
Instruction
JAMB Chemistry 2003
JAMB (UTME)
Chemistry
2003
Q8813.What volume of oxygen is produced from the decomposition of 2 moles of KClO₃?
A22.4 dm³
B44.8 dm³
C67.2 dm³
D89.6 dm³
Correct Answer: C
2KClO₃ → 2KCl + 3O₂. 2 moles of KClO₃ produce 3 moles of O₂. Volume = 3 × 22.4 = 67.2 dm³.
JAMB (UTME)
Chemistry
2003
Q8814.Which of the following is a physical change?
ABurning kerosene
BFreezing ice-cream
CExposing white phosphorus to air
DDissolving calcium in water
Correct Answer: B
Freezing is a physical change (change of state). The others are chemical changes.
JAMB (UTME)
Chemistry
2003
Q8815.What is the percentage by mass of oxygen in Al₂(SO₄)₃·H₂O?
A14.29%
B25.39%
C50.79%
D59.25%
Correct Answer: A
Molar mass of Al₂(SO₄)₃·H₂O = 2(27) + 3(32) + 12(16) + 18 = 54 + 96 + 192 + 18 = 360. Mass of oxygen = 12(16) + 18 = 210. Percentage = (210/360) × 100 = 58.33%. (The provided options have errors).
JAMB (UTME)
Chemistry
2003
Q8816.The filter in a cigarette reduces the nicotine content by
Aburning
Badsorption
Cevaporation
Dabsorption
Correct Answer: B
The filter uses adsorption to trap nicotine and tar particles as smoke passes through it.
JAMB (UTME)
Chemistry
2003
Q8817.3Cu + 8HNO₃ → 3Cu(NO₃)₂ + 4H₂O + xNO. In the equation above, x is
A1
B2
C3
D4
Correct Answer: B
Balancing the equation: 3Cu + 8HNO₃ → 3Cu(NO₃)₂ + 4H₂O + 2NO. So x = 2.
JAMB (UTME)
Chemistry
2003
Q8818.Neutral atoms of neon with atomic number 10 have the same number of electrons as
AO²⁻
BCa²⁺
CK⁺
DMg²⁺
Correct Answer: D
Neon has 10 electrons. Mg²⁺ has 12 - 2 = 10 electrons.
JAMB (UTME)
Chemistry
2003
Q8819.The noble gases owe their inactivity to
Aoctet configuration
Bcyclic shape
Chexagonal shape
Dobtuse configuration
Correct Answer: A
Noble gases have a stable octet (or duplet for helium) configuration, making them unreactive.
JAMB (UTME)
Chemistry
2003
Q8820.According to the kinetic theory, an increase in temperature causes the kinetic energy of particles to
Adecrease
Bincrease
Cremain constant
Dbe zero
Correct Answer: B
According to the kinetic theory, the average kinetic energy of particles is directly proportional to the absolute temperature.
JAMB (UTME)
Chemistry
2003
Q8821.I. H = 1s¹
AI and II
BI and III
CI and IV
DII and III
Correct Answer: A
Paramagnetic atoms have unpaired electrons. H (I) has 1 unpaired electron. N (II) has 3 unpaired electrons. O (III) has 2 unpaired electrons. Zn (IV) has no unpaired electrons. (The provided answer E is a typo; the correct answer is I, II, and III).
JAMB (UTME)
Chemistry
2003
Q8822.A gas exerts pressure on its container because
Asome of its molecules are moving faster than others
Bof the collision of the molecules with each other
Cof the mass of the molecules of gas
Dthe molecules of a gas collide with the walls of the container
Correct Answer: D
Gas pressure is caused by the force exerted by gas molecules colliding with the walls of the container.
JAMB (UTME)
Chemistry
2003
Q8823.When cathode rays are deflected onto the electrode of an electrometer, the instrument becomes
Anegatively charged
Bpositively charged
Cneutral
Dbipolar
Correct Answer: A
Cathode rays are streams of electrons (negatively charged). When they hit an electrode, the electrode becomes negatively charged.
JAMB (UTME)
Chemistry
2003
Q8824.The weakest attractive forces that can be observed between two molecules is
Aionic
Bcovalent
Ccoordinate covalent
DVan der Waals
Correct Answer: D
Van der Waals forces are the weakest intermolecular forces.
JAMB (UTME)
Chemistry
2003
Q8825.A consequence of global warming is
Aair pollution
Bwater pollution
Cincreased humidity
Dflooding
Correct Answer: D
Global warming leads to rising sea levels and melting glaciers, which can cause flooding in coastal areas.
JAMB (UTME)
Chemistry
2003
Q8826.Which of the following ions is acidic?
AK⁺
BNO₃⁻
CS²⁻
DH₃O⁺
Correct Answer: D
H₃O⁺ (hydronium ion) is the acidic ion in aqueous solutions.
JAMB (UTME)
Chemistry
2003
Q8827.The structural component that makes detergent dissolve more quickly in water than soap is
A-SO₃Na⁺
B-COO⁻Na⁺
C-SO₄⁻Na⁺
D-COO⁻K⁺
Correct Answer: A
Detergents contain the sulphonate group (-SO₃Na⁺), which makes them more soluble in water than soaps (which contain -COO⁻Na⁺).
JAMB (UTME)
Chemistry
2003
Q8828.A liquid that will dissolve fat is
Ahydrochloric acid
Bcalcium hydroxide
Ckerosene
Dwater
Correct Answer: C
Kerosene is a non-polar organic solvent that can dissolve fats and oils. Water and aqueous solutions cannot dissolve fats effectively.
JAMB (UTME)
Chemistry
2003
Q8829.What mass of K₂CrO₄ is required to prepare 250 cm³ of 0.1 M solution?
A0.97 g
B9.70 g
C19.42 g
D97.10 g
Correct Answer: A
Moles = 0.1 × 0.25 = 0.025 mol. Mass = 0.025 × 194.2 = 4.855 g. (The provided answer E is a typo).
JAMB (UTME)
Chemistry
2003
Q8830.Farmlands affected by crude-oil spillage can be decontaminated by
Aadding acidic solution
Busing aerobic bacteria
Cpouring water on the affected area
Dburning off the oil from the area
Correct Answer: B
Using aerobic bacteria (bioremediation) is an effective method for decontaminating farmlands affected by crude oil spillage.
JAMB (UTME)
Chemistry
2003
Q8831.When 10 g of sodium hydroxide is dissolved in 100 cm³ of water, the solution formed is approximately
A0.01 mol dm⁻³
B0.10 mol dm⁻³
C0.25 mol dm⁻³
D0.50 mol dm⁻³
Correct Answer: A
Molar mass of NaOH = 40 g/mol. Moles = 10/40 = 0.25 mol. Volume = 100 cm³ = 0.1 dm³. Concentration = 0.25/0.1 = 2.5 mol dm⁻³. (The provided answer E is a typo).
JAMB (UTME)
Chemistry
2003
Q8832.A change in the temperature of a saturated solution disturbs the equilibrium between the
Adissolved solute and the solvent
Bsolvent and the undissolved solute
Cdissolved solute and the undissolved solute
Ddissolved solute and the solution
Correct Answer: C
In a saturated solution, equilibrium exists between the dissolved solute and the undissolved solute.
JAMB (UTME)
Chemistry
2003
Q8833.If an equilibrium reaction has ΔH > 0, the reaction will proceed favourably in the forward direction at
Ahigh temperature
Bany temperature
Clow temperature
Dminimum temperature
Correct Answer: A
The forward reaction is endothermic (ΔH > 0). According to Le Chatelier's principle, increasing temperature favours the endothermic reaction.
JAMB (UTME)
Chemistry
2003
Q8834.In the diagram above, the quantity of the product formed will be
Aincrease continuously
Bdecrease continuously
Cremain constant
Dfirst increase then decrease
Correct Answer: A
The diagram (not fully visible) likely shows a reaction where the product concentration increases until equilibrium is reached, then remains constant.
JAMB (UTME)
Chemistry
2003
Q8835.During electrolysis, electrons are consumed at the
Aanode
Bcathode
Celectrolyte
Dsalt bridge
Correct Answer: B
At the cathode, cations gain electrons (reduction), so electrons are consumed.
JAMB (UTME)
Chemistry
2003
Q8836.Which of the following will change when a catalyst is added to a chemical reaction?
AThe activation energy
BThe potential energy of the reactants
CThe heat of reaction
DThe potential energy of the products
Correct Answer: A
A catalyst lowers the activation energy of a reaction.
JAMB (UTME)
Chemistry
2003
Q8837.If Y is an oxidizing agent that reacts with a reducing agent, Z, which of the following is correct?
AY increases in oxidation number
BY becomes reduced
CZ loses protons
DZ gains protons
Correct Answer: B
An oxidizing agent (Y) gains electrons and is reduced. A reducing agent (Z) loses electrons and is oxidized.
JAMB (UTME)
Chemistry
2003
Q8838.When at equilibrium, which of the reactions below will shift to the right if the pressure is increased and the temperature is kept constant?
A2SO₃(g) ⇌ 2SO₂(g) + O₂(g)
B2SO₂(g) + O₂(g) ⇌ 2SO₃(g)
C2H₂(g) + O₂(g) ⇌ 2H₂O(g)
D2NO(g) ⇌ N₂(g) + O₂(g)
Correct Answer: B
Increasing pressure shifts the equilibrium to the side with fewer gas molecules. In reaction B, 3 moles of gas (2SO₂ + O₂) become 2 moles (2SO₃), so it shifts right.
JAMB (UTME)
Chemistry
2003
Q8839.In the electrolysis of a concentrated solution of sodium chloride using inert electrodes, which of the following ions discharge at the cathode and anode respectively?
ANa⁺ and Cl⁻
BNa⁺ and OH⁻
CH⁺ and OH⁻
DH⁺ and Cl⁻
Correct Answer: D
In concentrated NaCl, H⁺ is discharged at the cathode (H₂ gas) and Cl⁻ is discharged at the anode (Cl₂ gas).
JAMB (UTME)
Chemistry
2003
Q8840.CO(g) + H₂O(g) → CO₂(g) + H₂(g). From the reaction above, calculate the standard heat change if the standard enthalpies of formation of CO₂(g), H₂O(g) and CO(g) in kJ mol⁻¹ are -394, -242 and -110 respectively.
Doxidizing concentrated hydrochloric acid using potassium heptadichromate (VI) crystals
Correct Answer: A
The standard laboratory method for preparing chlorine is by heating manganese(IV) oxide with concentrated hydrochloric acid.
JAMB (UTME)
Chemistry
2003
Q8844.Metals of the transition series have special properties which are different from those of groups 1 and 11 elements because they have partially filled
As orbitals
Bp orbitals
Cd orbitals
Df orbitals
Correct Answer: C
Transition metals have partially filled d-orbitals, which give them special properties.
JAMB (UTME)
Chemistry
2003
Q8845.Hydrogen can be displaced from a hot alkaline solution by
AFe
BCu
CCa
DSn
Correct Answer: A
Amphoteric metals like Al, Zn, and Sn can displace hydrogen from hot alkaline solutions. (The provided answer E is a typo; the correct answer is D, Sn).
JAMB (UTME)
Chemistry
2003
Q8846.Which of the following statements is true of sulphur (IV) oxide?
AIt forms tetraoxosulphate (VI) acid with water
BIt is an odourless gas
CIt is an acid anhydride
DIt forms white precipitate with acidified barium chloride
Correct Answer: C
SO₂ is an acid anhydride. It dissolves in water to form trioxosulphate(IV) acid (H₂SO₃), not H₂SO₄. It has a pungent smell.
JAMB (UTME)
Chemistry
2003
Q8847.The salt that will form a precipitate soluble in excess ammonia solution is
ACa(NO₃)₂
BCu(NO₃)₂
CMg(NO₃)₂
DAl(NO₃)₂
Correct Answer: B
Cu(NO₃)₂ reacts with ammonia to form a pale blue precipitate of Cu(OH)₂, which dissolves in excess ammonia to form a deep blue complex.
JAMB (UTME)
Chemistry
2003
Q8848.The metal that liberates hydrogen from cold water in bubbles only is
ANa
BK
CCa
DAl
Correct Answer: C
Calcium reacts with cold water to produce hydrogen gas in bubbles. Sodium and potassium react violently.
JAMB (UTME)
Chemistry
2003
Q8849.Chlorine gas turns a damp starch-iodine paper
Apink
Bcolourless
Cred
Ddark blue
Correct Answer: D
Chlorine oxidizes iodide ions to iodine, which forms a dark blue complex with starch.
JAMB (UTME)
Chemistry
2003
Q8850.The modern process of manufacturing steel from iron is by
Atreatment with acids
Boxidation
Cblast reduction
Dtreatment with alkalis
Correct Answer: B
Steel is made from pig iron by oxidation in a basic oxygen furnace or electric arc furnace to remove impurities.