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Instruction
JAMB Chemistry 2001
JAMB (UTME)
Chemistry
2001
Q8751.To make coloured glasses, small quantities of oxides of metals which form coloured silicates are often added to the reaction mixture consisting of Na₂CO₃ and SiO₂. Such a metal is
Apotassium
Bbarium
Czinc
Dcopper
Correct Answer: D
Copper compounds are added to glass to produce blue or green colours.
JAMB (UTME)
Chemistry
2001
Q8752.Which of the following compounds gives a yellow residue when heated and also reacts with aqueous sodium hydroxide to give a white gelatinous precipitate soluble in excess sodium hydroxide solution?
A(NH₄)₂CO₃
BZnCO₃
CAl₂(SO₄)₃
DPbCO₃
Correct Answer: B
ZnCO₃ gives a yellow residue (ZnO) when heated. It reacts with NaOH to give a white gelatinous precipitate of Zn(OH)₂, which dissolves in excess NaOH to form zincate.
JAMB (UTME)
Chemistry
2001
Q8753.A cycloalkane with molecular formula C₆H₁₂ has
Aone isomer
Btwo isomers
Cthree isomers
Dfour isomers
Correct Answer: A
C₆H₁₂ has several isomers including cyclohexane, methylcyclopentane, and various dimethylcyclobutanes and ethylcyclobutanes. (The provided answer E is a typo).
JAMB (UTME)
Chemistry
2001
Q8754.The structure of cis-2-butene is
ACH₃CH=CHCH₃
BCH₃CH=CHCH₃ (with CH₃ groups on same side)
CCH₃CH=CHCH₃ (with CH₃ groups on opposite sides)
DCH₃CH₂CH=CH₂
Correct Answer: B
In cis-2-butene, the two methyl groups are on the same side of the double bond.
JAMB (UTME)
Chemistry
2001
Q8755.What is the IUPAC name for the hydrocarbon CH₃CH₂C(CH₃)=CHCH₃?
A2-ethyl-4-methylpent-2-ene
B3,5-dimethylhex-3-ene
C2,4-dimethylhex-3-ene
D2-methyl-4-ethylpent-3-ene
Correct Answer: A
The longest chain containing the double bond has 6 carbons (hexene). The double bond is at position 3, with methyl groups at positions 2 and 4. The correct name is 2,4-dimethylhex-3-ene. (The provided answer E is a typo).
JAMB (UTME)
Chemistry
2001
Q8756.CH₃CH=CH₂ → P. Compound P, in the above reaction, is
ACH₃C≡CH
BCH₃CH₂CH₃
CCH₃CH₂CH₂OH
DCH₃CH₂CH₂NH₂
Correct Answer: B
The reaction is hydrogenation. Propene reacts with hydrogen to form propane (CH₃CH₂CH₃).
JAMB (UTME)
Chemistry
2001
Q8757.The label on a reagent bottle containing a clear organic liquid dropped off. The liquid was neutral to litmus and gave a colourless gas with metallic sodium. The liquid must be an
Aalkanoate
Balkene
Calkanol
Dalkane
Correct Answer: C
Alkanols (alcohols) are neutral to litmus and react with metallic sodium to produce hydrogen gas.
JAMB (UTME)
Chemistry
2001
Q8758.COOH + NaOH → COO⁻Na⁺ + H₂O
Adisplacement reaction
Ba neutralization reaction
Can elimination reaction
Dsaponification
Correct Answer: B
The reaction between a carboxylic acid and a base (NaOH) to form salt and water is neutralization.
JAMB (UTME)
Chemistry
2001
Q8759.Alkanoic acids have low volatility compared with alkanols because they
Aare more polar than alkanols
Bhave two oxygen atoms while alkanols have one
Cform two hydrogen bonds while alkanols form one
Dform more hydrogen bonds than alkanols
Correct Answer: C
Carboxylic acids form stronger hydrogen bonds (dimers) than alcohols, which increases their boiling points and reduces volatility.
JAMB (UTME)
Chemistry
2001
Q8760.The octane number of a fuel whose performance is the same as that of a mixture of 55 g of 2,2,4-trimethylpentane and 45 g of n-heptane is
A45
B55
C80
D100
Correct Answer: B
Octane number is the percentage of iso-octane (2,2,4-trimethylpentane) in the mixture. It is 55%.
JAMB (UTME)
Chemistry
2001
Q8761.Which of the following is formed when maltose reacts with concentrated tetraoxosulphate (VI) acid?
ACarbon (IV) oxide
BCoal tar
CCharcoal
DToxic fumes
Correct Answer: C
Concentrated H₂SO₄ dehydrates carbohydrates (like maltose) to produce black carbon (charcoal).
JAMB (UTME)
Chemistry
2001
Q8762.Which of the following compounds represents the polymerization product of ethyne?
ABenzene
BNaphthalene
CCyclohexane
DPolystyrene
Correct Answer: A
Ethyne (acetylene) polymerizes to form benzene when passed through a hot tube containing an organo-nickel catalyst.
Instruction
JAMB Chemistry 2002
JAMB (UTME)
Chemistry
2002
Q8763.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
2002
Q8764.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
2002
Q8765.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
2002
Q8766.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
2002
Q8767.3Cu + 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
2002
Q8768.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
2002
Q8769.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
2002
Q8770.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
2002
Q8771.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
2002
Q8772.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
2002
Q8773.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
2002
Q8774.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
2002
Q8775.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
2002
Q8776.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
2002
Q8777.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
2002
Q8778.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
2002
Q8779.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
2002
Q8780.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
2002
Q8781.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
2002
Q8782.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
2002
Q8783.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
2002
Q8784.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
2002
Q8785.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
2002
Q8786.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
2002
Q8787.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
2002
Q8788.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
2002
Q8789.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
2002
Q8790.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
2002
Q8794.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
2002
Q8795.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
2002
Q8796.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
2002
Q8797.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
2002
Q8798.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
2002
Q8799.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
2002
Q8800.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.