JAMB UTME - Chemistry - 1981

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Question 2 Rapport

Na₂CO₃ + 2HCI → 2NaCI + H₂O + CO₂. Using the above equation, what volume of carbondioxide, measured at s.t.p is liberated when 53g of sodium carbonate is dissolved in hydrochloric acid?
(1 mole of gas occupies 22.4 dm³ at s.t.p)
(Na = 23, C = 12, O = 16)

44.8 dm³

11.2 dm³ Bonne réponse

100.1 dm³

3.0 dm³

22.4 dm³

Détails de la réponse

Lisez la note de cours sur Stoichiometry And Chemical Reactions (WAEC)

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Question 3 Rapport

Which of the following statements about phosphorus is NOT correct?

Phosphorus is a solid mineral

Phosphorus is obtained by oxidation reaction of phosphate

Phosphorus exists in two allotropic forms

Both forms of phosphorus are interconvertible

Yellow phosporus ignites when rubbed on a rough surface Bonne réponse

Détails de la réponse

Lisez la note de cours sur Chemical Bonds (Nigeria Only) (WAEC)

Chemical Bonds (Nigeria Only)

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Question 4 Rapport

Which of the following processes takes place during electrolysis?

Positive ions are discharged at the anode bby gaining sufficient electrons to become neutral

Negative ions are dicharged at the anode by gaining suficient electrons to become neutral

Positive ions are discharged at the anode by losing sufficient electrons to become neutral

Negative ions are discharge at the anode by losing sufficient electrons to become neutral Bonne réponse

Nothing happens

Détails de la réponse

Lisez la note de cours sur Electrolysis (JAMB)

Electrolysis

Voir la réponse

Question 5 Rapport

The mass number of an atom is?

the number of electrons in the atom

the number of protons in the nucleus of the atom

the number of neutrons in the nucleus of the atom

the sum of numbers of electrons and protons inthe atom

the sum of numbers of proton and neutrons in the nucleus of the atom Bonne réponse

Détails de la réponse

Lisez la note de cours sur Atomic Structure And Bonding (JAMB)

Voir la réponse

Question 6 Rapport

An element X has 127 neutrons and 82 electrons.
Its atomic number is?

209

105

82 Bonne réponse

Détails de la réponse

Lisez la note de cours sur Atomic Structure And Bonding (JAMB)

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Question 7 Rapport

Pure sulphuric acid is a liquid of 1:84 density. What volume of it would be required to prepare 250 cm³ of 2.0 M solution?

(H = 1, S = 32, O = 16)

2.00

2.66 Bonne réponse

3.00

3.66

4.00

Détails de la réponse

Lisez la note de cours sur Kinetic Theory Of Matter And Gas Laws (JAMB)

Lisez la note de cours sur Stoichiometry And Chemical Reactions (WAEC)

Lisez la note de cours sur Acids, Bases And Salts (Ghana Only) (WAEC)

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Question 8 Rapport

An example of a strong electrolyte is?

ethyl acetate

ethanol

glucose

sodium formate Bonne réponse

formic acid

Détails de la réponse

Lisez la note de cours sur Electrolysis (JAMB)

Lisez la note de cours sur Acids, Bases And Salts (Ghana Only) (WAEC)

Electrolysis

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Question 9 Rapport

In the preparation of ammonia, which of the following is used as the drying agent?

CaO Bonne réponse

CaCI₂

Conc. H₂SO₄

P₂O₅

H₃PO₄

Détails de la réponse

Lisez la note de cours sur Acids, Bases And Salts (JAMB)

Acids, Bases And Salts

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Question 10 Rapport

If an organic compound decolorizes bromine water then the compound is?

saturated

supersaturated

unsaturated Bonne réponse

a solid

protonated

Détails de la réponse

Lisez la note de cours sur Electrolysis (JAMB)

Electrolysis

Voir la réponse

Question 11 Rapport

Which of the following can have an isomer?

C₂H₄

C₄H₁₀ Bonne réponse

C₃H₈

C₂H₆

C₆H₆

Détails de la réponse

Lisez la note de cours sur Acids, Bases And Salts (JAMB)

Acids, Bases And Salts

Voir la réponse

Question 12 Rapport

Fats and oils are?

addition products of long chain fatty acids and alkali

addition products of long-chain fattyy acids and glycerol

condensation products of long-chain fatty acids and glycerol Bonne réponse

condensation products of formaldehyde and glycerol

liquids at 20°C

Détails de la réponse

Lisez la note de cours sur Chemistry Of Carbon Compounds (Nigeria Only) (WAEC)

Lisez la note de cours sur Chemistry, Industry And The Environment (WAEC)

Lisez la note de cours sur Metals And Their Compounds (JAMB)

Chemistry Of Carbon Compounds (Nigeria Only)

Chemistry, Industry And The Environment

Metals And Their Compounds

Voir la réponse

Question 13 Rapport

If concentrated sulphric acid is added to sugar and warmed gently, the sugar changes from white to brown and finally to a black mas of carbon. In this reaction, concentrated sulphuric acid is acting as ?

a drying agent

an oxidizing agent

a dehydrated agent Bonne réponse

a reducing agent

a hydrolysing agent

Détails de la réponse

Lisez la note de cours sur Acids, Bases And Salts (JAMB)

Lisez la note de cours sur Oxidation And Reduction (JAMB)

Acids, Bases And Salts

Oxidation And Reduction

Voir la réponse

Question 14 Rapport

What happens when the nitrates of potassium, calcium, zinc and copper are separately heated?

All the nitrate will decompose to their respective metals

The nitrates of calcium and potassium will decomposes to their nitrites

Only copper nitrate decomposes to the metal

Only the nitrates of zinc and copper will decompose to their oxides

The nitrates of calcium, zinc and copper decompose to their oxides Bonne réponse

Détails de la réponse

Lisez la note de cours sur Acids, Bases And Salts (JAMB)

Acids, Bases And Salts

Voir la réponse

Question 15 Rapport

In the reaction
C + 2HNO₃ → CO₂ + NO₂ + NO + H₂O nitric acid is acting as?

a reducing agent

a nitrating agent

an oxidizing agent Bonne réponse

a catalytic agent

a neutralizing agent

Détails de la réponse

Lisez la note de cours sur Oxidation And Reduction (JAMB)

Oxidation And Reduction

Voir la réponse

Question 16 Rapport

The brown coloration in nitric acid prepared in the laboratory can be removed by?

heating the acid

bubbling air through the acid Bonne réponse

cooling the acid

adding a decolorizing agent

adding a base

Détails de la réponse

Lisez la note de cours sur Acids, Bases And Salts (Ghana Only) (WAEC)

Voir la réponse

Question 17 Rapport

When air is compressed?

its density decreases

it solidifies

its temperature decreases Bonne réponse

its temperature increases

its temperature remains unchanged

Détails de la réponse

Lisez la note de cours sur Kinetic Theory Of Matter And Gas Laws (JAMB)

Lisez la note de cours sur Separation Of Mixtures And Purification Of Chemical Substances (JAMB)

Separation Of Mixtures And Purification Of Chemical Substances

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Question 18 Rapport

When glowing splint is inserted into the mouth of a jar containing a gas, the splint is extinguished. The gas gives a white precipitate when passing into barium hydroxide. The gas is?

methane

hydrogen chloride

hydrogen

nitrogen

carbondioxide Bonne réponse

Détails de la réponse

Lisez la note de cours sur Kinetic Theory Of Matter And Gas Laws (JAMB)

Voir la réponse

Question 19 Rapport

The scale formation in a kinetic used for boiling water is caused by the presence in water of?

calcium sulphate

calcium carbonate

calcium hydrogen carbonate Bonne réponse

calcium hydroxide

magnesium sulphate

Détails de la réponse

Lisez la note de cours sur Solubility Of Substances (Ghana Only) (WAEC)

Lisez la note de cours sur Water (JAMB)

Solubility Of Substances (Ghana Only)

Water

Voir la réponse

Question 20 Rapport

Sodium and potassium belong to the same group of the Periodic Table. This is because?

both are metals

both are soft and lighter than water

both form cations by losing electrons Bonne réponse

both have identical electronic configuration

both react with water vigorously

Détails de la réponse

Lisez la note de cours sur Periodic Chemistry (Nigeria Only) (WAEC)

Periodic Chemistry (Nigeria Only)

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Question 21 Rapport

Oxidation is the process of?

gain of electrons

loss of electrons Bonne réponse

gain of hydrogen

loss of oxygen

addition of an electropositive element to a substance

Détails de la réponse

Lisez la note de cours sur Oxidation And Reduction (JAMB)

Oxidation And Reduction

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Question 22 Rapport

For iron to rust, there should be present?

oxygen

moisture

carbondioxide

oxygen and moisture Bonne réponse

oxygen, moisture and carbondioxide

Détails de la réponse

Lisez la note de cours sur Energy And Energy Changes (WAEC)

Energy And Energy Changes

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Question 23 Rapport

The following compounds are given with their corresponding boiling points.
Compound Boiling Point
i.................................14°C
ii................................24°C
iii................................0°C
iv................................120°C
V.................................-2°C
From the above information, indicate which of the following is correct?

All the compounds are gaseous at 20 °C

One of the compounds is gaseous at 20 °C

Two of the compounds are gaseous at 20 °C

Three of the compounds are gaseous at 20 °C Bonne réponse

None of the compounds is gaseous at 20 °C

Détails de la réponse

Lisez la note de cours sur Kinetic Theory Of Matter And Gas Laws (JAMB)

Voir la réponse

Question 24 Rapport

4g each of aluminium foil and aluminium powder were introduced respectively into flasks P and Q.
Flask P was treated with warm bench sodium hydroxide and all the aluminium dissolved in one hour. Flask Q was treated with cold sodium hydroxide and all the aluminium dissolved in 10 minutes. What was responsible for Q reacting faster than P?

There were more aluminium atoms in Q than P

The heat given off in retarded the reaction

Q generated more pressure than P during the reaction

P generated more pressure than Q

Q has a greater surface area for the reaction than P Bonne réponse

Détails de la réponse

Lisez la note de cours sur Chemical Combination (JAMB)

Chemical Combination

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Question 25 Rapport

Which of the following represents a precipitation reaction?

H₂SO₄ + NaCl \(\to\) NaHSO₄ + HCl

Fe +H₂SO₄ \(\to\) FeSO₄ + H₂

4HCl + MnO₂ \(\to\) MnCl₂ + 2H₂O + Cl₂

Na₂SO₄ + pb(NO₃) \(\to\) PbSO₄ + 2NaNO Bonne réponse

CuO +2HCl \(\to\) Cl₂ + H₂O

Détails de la réponse

Lisez la note de cours sur Kinetic Theory Of Matter And Gas Laws (JAMB)

Lisez la note de cours sur Stoichiometry And Chemical Reactions (WAEC)

Lisez la note de cours sur Acids, Bases And Salts (Ghana Only) (WAEC)

Voir la réponse

Question 26 Rapport

Allotropes are elements having?

different physical but the same chemical properties Bonne réponse

different chemical but the same physical properties

the same chemical and physical properties

different atomic structure

the same position in the periodic table

Détails de la réponse

Lisez la note de cours sur Chemical Equilibria (JAMB)

Chemical Equilibria

Voir la réponse

Question 27 Rapport

When a bottle of Coca-Cola is opened, bubbles of evolve. The gas is?

hydrogen

carbon monoxide

carbon dioxide Bonne réponse

sulphur oxide

chlorine

Détails de la réponse

Lisez la note de cours sur Kinetic Theory Of Matter And Gas Laws (JAMB)

Voir la réponse

Question 28 Rapport

Which of the following is the electronic configuration of sodium?
(Atomic number of Na = 11)

1s² 2s²2p⁶ 3s²

1s² 2s²2p⁶ 3s² 3p1s² 2s²2p⁶ 3s¹

1s² 2s²2p⁶ 3s¹ Bonne réponse

1s² 2s²2p⁶ 3s^°

1s² 2s²2p⁶ 4s¹

Détails de la réponse

Lisez la note de cours sur Atomic Structure And Bonding (JAMB)

Voir la réponse

Question 29 Rapport

In the reaction of oxygen with hydrogen to produce water, which of the following statements is true?

One atom of hydrogen reacts with two atoms of oxygen to give one molecule of water

Two atoms of hydrogen react with two atoms of oxygen to give two molecules of water

One molecule of oxygen reacts with one molecule of hydrogen to give two molecules of water

One molecule of hydrogen reaccts with two molecules of oxygen to give three molecules of water

One molecule of oxygen reacts with two molecules of hydrogen to give two molecules of water Bonne réponse

Détails de la réponse

Lisez la note de cours sur Chemical Combination (JAMB)

Chemical Combination

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Question 30 Rapport

An efflorescent compound is a substance that?

absorbs water froom the air without dissolving in it

is capable of giving off coloured luminosity

gives out water to the atmosphere Bonne réponse

absorbs water from the air and dissolves in it

gives out its water of crystallization on heating

Détails de la réponse

Lisez la note de cours sur Kinetic Theory Of Matter And Gas Laws (JAMB)

Voir la réponse

Question 31 Rapport

28.8 cm³ of nitrogen at 15°C is cooled to O°C at constant pressure, the new volume of nitrogen is?

17.4 cm³

14.7 cm³

27.3 cm³ Bonne réponse

31.7 cm³

Détails de la réponse

Lisez la note de cours sur Kinetic Theory Of Matter And Gas Laws (JAMB)

Voir la réponse

Question 32 Rapport

Which of the following is NOT a true statement of the kinetic Theory of Gases?

The molecules move at random

The size of molecules is negligble as compared with the volume of gas

The molecular collisions are perfectly elastic

Every molecule has the same kinetic energy at a particular temperature Bonne réponse

The average kinetic energy is proportional to the absolute temperature of the gas

Détails de la réponse

Lisez la note de cours sur Kinetic Theory Of Matter And Gas Laws (JAMB)

Voir la réponse

Question 33 Rapport

A polymerization reaction is one in which?

small molecules form giant molecules Bonne réponse

atoms form molecules

giant molecules form small molecules

molecules form volatile compounds

a molecule rearranges itself

Détails de la réponse

Lisez la note de cours sur Basic Biochemistry And Synthetic Polymers (WAEC)

Basic Biochemistry And Synthetic Polymers

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Question 34 Rapport

In the extraction of iron, which of the following reactions does NOT take place in the blast furnace?

CO₂ + C → 2CO

2Fe₂O₃ + 3C → 4Fe + 3CO₂ Bonne réponse

Fe₂O₃ + 3C → 2Fe + 3CO₂

CaCO₃ → CaO + CO₂

CaO + SiO₂ → CaSiO₃

Détails de la réponse

Lisez la note de cours sur Chemical Combination (JAMB)

Chemical Combination

Voir la réponse

Question 35 Rapport

the number of atoms in one mole of a substance is equal to?

the atomic number

the avogadro number Bonne réponse

the gas constant

the number of neutrons

the number of electrons

Détails de la réponse

Lisez la note de cours sur Structure Of The Atom (WAEC)

Structure Of The Atom

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Question 36 Rapport

The oxidation number of manganese in KMnO₄ is?

+7 Bonne réponse

Détails de la réponse

Lisez la note de cours sur Oxidation And Reduction (JAMB)

Oxidation And Reduction

Voir la réponse

Question 37 Rapport

Which of the following compounds and elements would sublime on exposure to the atmosphere?

Ice

Sulphur

Phosphurous

Iodine Bonne réponse

Potassium iodie

Détails de la réponse

Lisez la note de cours sur Kinetic Theory Of Matter And Gas Laws (JAMB)

Lisez la note de cours sur Non-metals And Their Compounds (JAMB)

Non-metals And Their Compounds

Voir la réponse

Question 38 Rapport

What mass of sodium carbonate solution is in 500 cm³ of 0.1 molar sodium carbonate solution?

(Na = 23, C = 12, O = 16)

10.6 g

5.3 g Bonne réponse

500 g

10 g

20 g

Détails de la réponse

Lisez la note de cours sur Stoichiometry And Chemical Reactions (WAEC)

Voir la réponse

Question 39 Rapport

If 48,000 coulombs of electricity are required to discharge 0.5 mole of sodium from a molten sodium chloride mass, then the number of coulombs required to discharge 2 moles of lead from molten lead (ll) chloride is?

48,000

96,000

192,000

384,000 Bonne réponse

576,000

Détails de la réponse

Lisez la note de cours sur Electrolysis (JAMB)

Lisez la note de cours sur Stoichiometry And Chemical Reactions (WAEC)

Electrolysis

Voir la réponse

Question 40 Rapport

When hydrogen sulphide and sulphur dioxide are each passed in turn into a solution of potassium dichromate?

both gases change the colour of the solution from yellow to colourless

both gases causes sulphur to be deposited

only hydrogen sulphide decolourizes the solution

only sulphur dioxide deposits sulphur

only hydrogen sulphide deposits sulphur Bonne réponse

Détails de la réponse

Lisez la note de cours sur Acids, Bases And Salts (JAMB)

Acids, Bases And Salts

Voir la réponse

Question 41 Rapport

The IUPAC name for

1-methlpentane

3-methylbutane

2-methylbutane Bonne réponse

1-dimethylpropane

2-methylpentane

Détails de la réponse

Lisez la note de cours sur Chemistry Of Carbon Compounds (Nigeria Only) (WAEC)

Chemistry Of Carbon Compounds (Nigeria Only)

Voir la réponse

Question 42 Rapport

Which one of the following metals is not normally extracted by chemical reduction because of its position in the electrochemical series?

Copper

Iron

Lead

Potassium Bonne réponse

Zinc

Détails de la réponse

Lisez la note de cours sur Metals And Their Compounds (JAMB)

Lisez la note de cours sur Non-metals And Their Compounds (JAMB)

Metals And Their Compounds

Non-metals And Their Compounds

Voir la réponse

Question 43 Rapport

Methane is member of the homologous series called?

alkenes

alcohols

esters

alkanes Bonne réponse

alkynes

Détails de la réponse

Lisez la note de cours sur Periodic Chemistry (Ghana Only) (WAEC)

Periodic Chemistry (Ghana Only)

Voir la réponse

Question 44 Rapport

The products of the reaction between dilute sulphuric acid and sodium thiosulphate crystals are?

Na₂SO₄ + SO₂ + O₂ + H₂O

Na₂SO₃ + SO₃ + O₂ + H₂O

Na₂SO₄ + SO₂ + S + H₂O Bonne réponse

Na₂SO₄ + SO₃ + S + H₂O

Na₂SO₄ + SO₂ + H₂O only

Détails de la réponse

Lisez la note de cours sur Acids, Bases And Salts (JAMB)

Acids, Bases And Salts

Voir la réponse

Question 45 Rapport

Which of the following statements is NOT true of electrovalent compounds?

They are solids

They do not vaporized easily

They usually dissolve in water

The elements forming the compounds normally have their valency electrons in a shared state Bonne réponse

They conduct electricity

Détails de la réponse

Voir la réponse

Question 46 Rapport

If one mole of aluminium contains 6 x 10²³ atoms of aluminium, how many atoms are contained in 0.9g of aluminium?
(Al = 27)

1.0 x 10²¹

6.6 x 10²¹

2.0 x 10²² Bonne réponse

1.0 x 10²²

5.4 x 10²³

Détails de la réponse

Lisez la note de cours sur Kinetic Theory Of Matter And Gas Laws (JAMB)