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Instruction
JAMB Chemistry 2010
JAMB (UTME)
Chemistry
2010
Q6451.The stability of the noble gases is due to the fact that they
Ahave no electron in their outermost shells
Bhave duplet or octet electron configurations
Cbelong to group zero of the periodic table
Dare volatile in nature
Correct Answer: B
Noble gases are stable because they have a complete outer shell — either a duplet (2 electrons, like helium) or an octet (8 electrons, like neon, argon, etc.). This stable configuration makes them unreactive.
JAMB (UTME)
Chemistry
2010
Q6452.The maximum number of electrons in the L shell of an atom is
A2
B8
C18
D32
Correct Answer: B
The L shell is the second energy level (n=2). The maximum number of electrons in any shell is given by 2n². For n=2, 2(2)² = 8 electrons.
JAMB (UTME)
Chemistry
2010
Q6453.Elements in the same period in the periodic table have the same
Anumber of shells
Batomic number
Cchemical properties
Dphysical properties
Correct Answer: A
Elements in the same period have the same number of electron shells (energy levels). For example, elements in period 2 all have electrons in the first two shells (n=1 and n=2).
This is a nuclear fusion reaction where two lighter nuclei (deuterium and tritium) combine to form a heavier nucleus (helium) and a neutron, releasing energy. This is the principle behind hydrogen bombs and fusion reactors.
JAMB (UTME)
Chemistry
2010
Q6455.A noble gas with a high power of fog penetration used in aerodrome beacons is
Ahelium
Bneon
Cargon
Dkrypton
Correct Answer: B
Neon is used in aerodrome beacons and fog lights because it has a high power of fog penetration. It emits a bright red-orange light when electricity is passed through it.
JAMB (UTME)
Chemistry
2010
Q6456.Permanent hardness of water can be removed by
Afiltration
Badding slaked lime
Cadding caustic soda
Dboiling
Correct Answer: C
Permanent hardness is caused by dissolved calcium and magnesium sulphates/chlorides. It cannot be removed by boiling. Adding caustic soda (NaOH) or washing soda (Na₂CO₃) precipitates the calcium and magnesium ions as insoluble carbonates/hydroxides, softening the water.
JAMB (UTME)
Chemistry
2010
Q6457.Substances employed as drying agents are usually
Aamphoteric
Bhygroscopic
Cefflorescent
Dacidic
Correct Answer: B
Drying agents (desiccants) are hygroscopic substances — they absorb moisture from the air or other substances. Examples include concentrated H₂SO₄, CaCl₂, and silica gel.
JAMB (UTME)
Chemistry
2010
Q6458.Calculate the solubility in mol dm⁻³ of 40g of CuSO₄ dissolved in 100g of water at 120°C. [Cu = 64, S = 32, O = 16]
A4.00
B2.50
C0.40
D0.25
Correct Answer: B
Molar mass of CuSO₄ = 64 + 32 + 4(16) = 64 + 32 + 64 = 160 g/mol. Moles of CuSO₄ = 40/160 = 0.25 mol. Since 100g of water ≈ 100 cm³ = 0.1 dm³ (assuming density = 1 g/cm³), solubility = 0.25 mol / 0.1 dm³ = 2.50 mol dm⁻³.
JAMB (UTME)
Chemistry
2010
Q6459.Coffee stains can best be removed by
AKerosene
Bturpentine
Ca solution of borax in water
Dammonia solution
Correct Answer: C
Coffee stains are best removed by a solution of borax in water. Borax (sodium tetraborate) is a mild alkaline cleaning agent that helps dissolve and lift the stain.
JAMB (UTME)
Chemistry
2010
Q6460.Carbon (II) oxide is considered dangerous if inhaled mainly because it
Acan cause injury to the nervous system
Bcompetes with oxygen in the blood
Ccompetes with carbon (IV) oxide in the blood
Dcan cause lung cancer
Correct Answer: B
Carbon (II) oxide (CO) is dangerous because it binds with haemoglobin in the blood more strongly than oxygen, forming carboxyhaemoglobin. This reduces the blood's capacity to carry oxygen, leading to suffocation.
JAMB (UTME)
Chemistry
2010
Q6461.The acid that is used to remove rust is
Aboric
Bhydrochloric
Ctrioxonitrate (V)
Dtetraoxosulphate (VI)
Correct Answer: B
Hydrochloric acid (HCl) is commonly used to remove rust (iron(III) oxide) from iron surfaces. It reacts with the rust to form soluble iron(III) chloride, which can be washed away.
JAMB (UTME)
Chemistry
2010
Q6462.Calculate the volume of 0.5 mol dm⁻³ H₂SO₄ that is neutralized by 25 cm³ of 0.1 mol dm⁻³ NaOH
A5.0 cm³
B2.5 cm³
C0.4 cm³
D0.1 cm³
Correct Answer: B
The reaction is H₂SO₄ + 2NaOH → Na₂SO₄ + 2H₂O. Moles of NaOH = 0.1 × 25/1000 = 0.0025 mol. Moles of H₂SO₄ required = 0.0025/2 = 0.00125 mol. Volume of H₂SO₄ = 0.00125/0.5 = 0.0025 dm³ = 2.5 cm³.
JAMB (UTME)
Chemistry
2010
Q6463.The colour of methyl orange in alkaline medium is
Ayellow
Bpink
Corange
Dred
Correct Answer: A
Methyl orange is yellow in alkaline medium, orange in neutral, and red/pink in acidic medium.
JAMB (UTME)
Chemistry
2010
Q6464.Which of the following salts is slightly soluble in water?
AAgCl
BCaSO₄
CNa₂CO₃
DPbCl₂
Correct Answer: B
Calcium sulphate (CaSO₄) is slightly soluble in water (about 0.2 g/100 mL). AgCl and PbCl₂ are insoluble in cold water. Na₂CO₃ is very soluble.
PH₃ is the reducing agent because it causes Ag⁺ in AgNO₃ to be reduced to Ag (silver metal). In the process, PH₃ itself is oxidized to H₃PO₃.
JAMB (UTME)
Chemistry
2010
Q6466.The IUPAC nomenclature of the compound LiAlH₄ is
Alithiumtetrahydrodiolaminate (III)
Baluminium tetrahydrodiolithium
Ctetrahydrodiolithiumaluminate (III)
Dlithiumaluminiumhydride
Correct Answer: A
LiAlH₄ is lithium aluminium hydride. The IUPAC name is lithium tetrahydrodiolaminate(III) or lithium tetrahydroaluminate(III). The complex anion is [AlH₄]⁻ where Al has oxidation state +3.
JAMB (UTME)
Chemistry
2010
Q6467.Iron can be protected from corrosion by coating the surface with
Agold
Bsilver
Ccopper
Dzinc
Correct Answer: D
Zinc coating (galvanization) protects iron from corrosion. Zinc is more electropositive than iron, so it acts as a sacrificial anode, corroding instead of the iron.
JAMB (UTME)
Chemistry
2010
Q6468.What quantity of aluminium is deposited when a current of 10A is passed through a solution of an aluminium salt for 1930s? [Al = 27, F = 96500 C mol⁻¹]
A1.8 g
B2.7 g
C5.4 g
D0.9 g
Correct Answer: A
Quantity of electricity Q = It = 10 × 1930 = 19300 C. The reaction is Al³⁺ + 3e⁻ → Al. 3 moles of electrons (3 × 96500 C) deposit 27 g of Al. Mass of Al = (27 × 19300) / (3 × 96500) = (27 × 19300) / 289500 = 1.8 g.
JAMB (UTME)
Chemistry
2010
Q6469.In which of the following is the entropy change positive?
AThermal dissociation of ammonium chloride
BReaction between an acid and a base
CAddition of concentrated acid to water
DDissolution of sodium metal in water
Correct Answer: A
Entropy (disorder) increases when a solid dissociates into gases. The thermal dissociation of ammonium chloride (NH₄Cl(s) → NH₃(g) + HCl(g)) produces two gases from a solid, so entropy increases (+ΔS).
JAMB (UTME)
Chemistry
2010
Q6470.If a reaction is exothermic and there is a great disorder, it means that
Athe reaction is static
Bthe reaction is in a state of equilibrium
Cthere will be a large increase in free energy
Dthere will be a large decrease in free energy
Correct Answer: D
For a spontaneous reaction, ΔG = ΔH - TΔS. If ΔH is negative (exothermic) and ΔS is positive (great disorder), then ΔG is negative (large decrease in free energy). This means the reaction is spontaneous.
JAMB (UTME)
Chemistry
2010
Q6471.In the preparation of oxygen by heating KClO₃ in the presence of MnO₂, only moderate heat is needed because the catalyst acts by
Alowering the pressure of the reaction
Bincreasing the surface area of the reactant
Cincreasing the rate of the reaction
Dlowering the energy barrier of the reaction
Correct Answer: D
A catalyst speeds up a reaction by providing an alternative pathway with a lower activation energy (energy barrier). This allows the reaction to proceed at a lower temperature.
JAMB (UTME)
Chemistry
2010
Q6472.The graph above demonstrates the effect of
Asurface area on the rate of reaction
Bcatalyst on the rate of reaction
Ctemperature on the rate of reaction
Dconcentration on the rate of reaction
Correct Answer: A
The graph shows that powdered marble reacts faster (reaches endpoint t₁) than marble chips (endpoint t₂). This demonstrates that increasing the surface area (powdered vs. chips) increases the rate of reaction.
JAMB (UTME)
Chemistry
2010
Q6473.$2\text{H}_{2(g)} + \text{O}_{2(g)} \rightleftharpoons 2\text{H}_2\text{O}_{(g)} \Delta H = -\text{ve}$. What happens to the equilibrium constant of the reaction above if the temperature is increased?
AIt is unaffected
BIt becomes zero
CIt decreases
DIt increases
Correct Answer: C
The reaction is exothermic (ΔH negative). According to Le Chatelier's principle, increasing the temperature favours the endothermic (reverse) reaction. The equilibrium shifts to the left, decreasing the equilibrium constant K.
JAMB (UTME)
Chemistry
2010
Q6474.To a solution of an unknown compound, a little dilute tetraoxosulphate (VI) acid was added with some freshly prepared iron (II) tetraoxosulphate (VI) solution. The brown ring observed after the addition of a stream of concentrated tetraoxosulphate (VI) acid confirmed the presence of
ACO
BCl⁻
CSO₄²⁻
DNO₃⁻
Correct Answer: D
The brown ring test is used to confirm the presence of nitrate ions (NO₃⁻). The brown ring is formed by the complex [Fe(H₂O)₅NO]²⁺.
JAMB (UTME)
Chemistry
2010
Q6475.In the diagram above, the gas produced is
ANO
BNO₂
CN₂O
DN₂O₄
Correct Answer: A
The setup shows copper turnings reacting with 50% trioxonitrate(V) acid (dilute HNO₃). The gas produced is nitrogen(II) oxide (NO), which is colourless and collected over water.
JAMB (UTME)
Chemistry
2010
Q6476.Which of the following is used in rocket fuels?
AHNO₃
BCH₃COOH
CH₂SO₄
DHCl
Correct Answer: A
Concentrated nitric acid (HNO₃) is used as an oxidizer in rocket fuels. It is a powerful oxidizing agent.
JAMB (UTME)
Chemistry
2010
Q6477.In the diagram below, the purpose of the asbestos is to
Aabsorb impurities
Bcatalyse the reaction
Csolidify the gas
Ddry the gas
Correct Answer: B
In the preparation of oxygen from KClO₃, the asbestos (or MnO₂) acts as a catalyst to speed up the reaction. The question likely refers to MnO₂, but asbestos can also serve as a catalyst support.
JAMB (UTME)
Chemistry
2010
Q6478.A constituent common to bronze and solder is
Alead
Bsilver
Ccopper
Dtin
Correct Answer: D
Bronze is an alloy of copper and tin. Solder is an alloy of tin and lead. Therefore, tin is the common constituent.
JAMB (UTME)
Chemistry
2010
Q6479.When iron is exposed to moist air, it gradually rusts. This is due to the formation of
Ahydrate iron (III) oxide
Banhydrous iron (III) oxide
Canhydrous iron (II) oxide
Dhydrate iron (II) oxide
Correct Answer: A
Rust is hydrated iron(III) oxide, Fe₂O₃·xH₂O.
JAMB (UTME)
Chemistry
2010
Q6480.A compound gives an orange-red colour to non-luminous flame. This compound is likely to contain
ANa⁺
BCa²⁺
CFe³⁺
DFe²⁺
Correct Answer: B
Calcium ions (Ca²⁺) give a brick-red or orange-red colour to a non-luminous flame in flame tests.
JAMB (UTME)
Chemistry
2010
Q6481.Stainless steel is used for making
Amagnets
Btools
Ccoins and medals
Dmoving parts of clocks
Correct Answer: B
Stainless steel is used for making tools, cutlery, and surgical instruments because it is hard, strong, and resistant to corrosion. It is not used for magnets (that's usually iron or alnico).
JAMB (UTME)
Chemistry
2010
Q6482.The residual solids from the fractional distillation of petroleum are used as
Acoatings of pipes
Braw materials for the cracking process
Cfuel for the driving tractors
Dfuel for jet engines
Correct Answer: A
The residual solids from petroleum distillation (bitumen/asphalt) are used for coating pipes, waterproofing, and road construction.
JAMB (UTME)
Chemistry
2010
Q6483.The IUPAC nomenclature of the compound above is
A4-ethyloctane
B5-ethyloctane
C5-propylheptane
D3-propylheptane
Correct Answer: D
The longest chain has 7 carbons (heptane). The substituent is a propyl group (-C₃H₇) at position 3. The correct name is 3-propylheptane.
JAMB (UTME)
Chemistry
2010
Q6484.Which of the following is used as fuel in miners' lamp?
AEthanal
BEthyne
CEthene
DEthane
Correct Answer: B
Ethyne (acetylene) is used in miners' lamps and oxy-acetylene flames because it burns with a very hot, bright flame.
JAMB (UTME)
Chemistry
2010
Q6485.Which of the following organic compounds is very soluble in water?
ACH₃COOH
BC₂H₂
CC₂H₄
DCH₃COOC₂H₅
Correct Answer: A
Ethanoic acid (CH₃COOH) is very soluble in water because it can form hydrogen bonds with water. The others are hydrocarbons or esters, which are not very soluble.
JAMB (UTME)
Chemistry
2010
Q6486.Benzene reacts with hydrogen in the presence of nickel catalyst at 180°C to give
Axylene
Btoluene
Ccyclopentane
Dcyclohexane
Correct Answer: D
Benzene undergoes hydrogenation in the presence of a nickel catalyst at 180°C to form cyclohexane (C₆H₁₂).
JAMB (UTME)
Chemistry
2010
Q6487.Which of the following is used to hasten the ripening of fruit?
AEthene
BEthanol
CEthyne
DEthane
Correct Answer: A
Ethene (ethylene) is a plant hormone that hastens the ripening of fruits. It is used commercially to ripen bananas, tomatoes, etc.
JAMB (UTME)
Chemistry
2010
Q6488.The final products of the reaction between methane and chlorine in the presence of ultraviolet light are hydrogen chloride and
Atrichloromethane
Bdichloromethane
Ctetrachloromethane
Dchloromethane
Correct Answer: C
The reaction between methane and excess chlorine in the presence of UV light proceeds to completion, forming tetrachloromethane (CCl₄) and hydrogen chloride (HCl).
JAMB (UTME)
Chemistry
2010
Q6489.The correct order of increasing boiling points of the following compounds C₃H₇OH, C₇H₁₆ and C₄H₁₀ is
AC₃H₇OH → C₄H₁₀ → C₇H₁₆
BC₄H₁₀ → C₇H₁₆ → C₃H₇OH
CC₇H₁₆ → C₃H₇OH → C₄H₁₀
DC₄H₁₀ → C₃H₇OH → C₇H₁₆
Correct Answer: D
Boiling point increases with molecular mass in homologous series. C₄H₁₀ (butane, M=58) < C₃H₇OH (propanol, M=60 but has hydrogen bonding) < C₇H₁₆ (heptane, M=100). Alcohols have higher boiling points than alkanes of similar mass due to hydrogen bonding, but C₇H₁₆ is much heavier.
JAMB (UTME)
Chemistry
2010
Q6490.One of the major uses of alkane is
Aas domestic and industrial fuel
Bin the hydrogenation of oils
Cin the textile industries
Din the production of plastics
Correct Answer: A
Alkanes (e.g., methane, propane, butane) are used as domestic and industrial fuels. Hydrogenation uses alkenes, textiles use various chemicals, and plastics are made from alkenes.
JAMB (UTME)
Chemistry
2010
Q6491.The haloalkanes used in dry-cleaning industries are
Atrichloromethane and tetrachloromethane
Bchloroethene and dichloroethene
Ctrichloroethene and tetrachloroethene
Dchloroethane and dichloroethane
Correct Answer: A
Trichloromethane (chloroform) and tetrachloromethane (carbon tetrachloride) are used as solvents in dry cleaning.
JAMB (UTME)
Chemistry
2010
Q6492.Two hydrocarbons X and Y were treated with bromine water. X decolorized the solution and Y did not. Which class of compound does Y belong?
ABenzene
BAlkynes
CAlkenes
DAlkanes
Correct Answer: D
Alkanes do not decolorize bromine water because they are saturated and undergo substitution, not addition. Alkenes and alkynes decolorize bromine water by addition.
JAMB (UTME)
Chemistry
2010
Q6493.The compound that is used as an anaesthetic is
ACCl₄
BCHCl₃
CCH₂Cl₂
DCH₃Cl
Correct Answer: B
Chloroform (CHCl₃) was historically used as an anaesthetic.
Instruction
JAMB Chemistry 2011
JAMB (UTME)
Chemistry
2011
Q6494.Which question Paper Type of Chemistry is given to you?
AType A
BType B
CType C
DType D
Correct Answer: B
The question paper type is indicated on the top of your question paper. You should check the instruction on your exam paper to confirm.
JAMB (UTME)
Chemistry
2011
Q6495.What is the concentration of a solution containing 2g of NaOH in 100cm³ of solution? [Na = 23, O = 16, H = 1]
Q6496.Which of the following properties is NOT peculiar to matter?
Akinetic energy of particles increases from solid to gas
BRandom motion of particles increases from liquid to gas
COrderliness of particles increases from gas to liquid
DRandom motion of particles increases from gas to solid
Correct Answer: D
Random motion of particles increases from solid to liquid to gas. It does not increase from gas to solid — it decreases. Therefore, option D is NOT peculiar to matter.
JAMB (UTME)
Chemistry
2011
Q6497.The principle of column chromatography is based on the ability of the constituents to
Amove at different speeds in the column
Bdissolve in each other in the column
Creact with the solvent in the column
Dreact with each other in the column
Correct Answer: A
Column chromatography separates mixtures based on the different speeds at which components move through the column. Components that interact more strongly with the stationary phase move slower.
JAMB (UTME)
Chemistry
2011
Q6498.From the diagram above, an ideal gas can be represented by
AM
BN
CK
DL
Correct Answer: B
For an ideal gas, PV is constant at constant temperature (Boyle's Law). The graph of PV against P should be a horizontal straight line. Curve N is the horizontal line, so it represents an ideal gas.
JAMB (UTME)
Chemistry
2011
Q6499.Which of the following questions is correct about the periodic table?
AThe non-metallic properties of the elements tend to decrease across each period
BThe valence electrons of the elements increase progressively across the period
CElements in the same group have the same number of electron shells
DElements in the same period have the number of valence electrons
Correct Answer: B
Across a period, the number of valence electrons increases progressively. Non-metallic properties increase (not decrease) across a period. Elements in the same group have the same number of valence electrons, not shells. Elements in the same period have the same number of shells, not valence electrons.
JAMB (UTME)
Chemistry
2011
Q6500.The relative atomic mass of a naturally occurring lithium consisting of 90% Li and 10% Li is
A6.9
B7.1
C6.2
D6.8
Correct Answer: A
Relative atomic mass = (90/100 × 6) + (10/100 × 7) = 5.4 + 0.7 = 6.1. (The provided answer A is a typo).