JAMB UTME - Chemistry - 1981

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Question 2 Report

The electronic configuration of elements X and Y are X = 2, 8, 6; Y = 2, 8, 7. The bond in the compound formed by X and Y is expected to be?

ionic

covalent Correct answer

dative covalent

metallic

none of the above

Answer Details

Read lesson note on Atomic Structure And Bonding (JAMB)

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Question 3 Report

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

209

105

82 Correct answer

Answer Details

Read lesson note on Atomic Structure And Bonding (JAMB)

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Question 4 Report

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 Correct answer

both have identical electronic configuration

both react with water vigorously

Answer Details

Read lesson note on Periodic Chemistry (Nigeria Only) (WAEC)

Periodic Chemistry (Nigeria Only)

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Question 5 Report

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 Correct answer

1s² 2s²2p⁶ 3s^°

1s² 2s²2p⁶ 4s¹

Answer Details

Read lesson note on Atomic Structure And Bonding (JAMB)

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Question 6 Report

Methane is member of the homologous series called?

alkenes

alcohols

esters

alkanes Correct answer

alkynes

Answer Details

Read lesson note on Periodic Chemistry (Ghana Only) (WAEC)

Periodic Chemistry (Ghana Only)

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Question 7 Report

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 Correct answer

a reducing agent

a hydrolysing agent

Answer Details

Read lesson note on Acids, Bases And Salts (JAMB)

Read lesson note on Oxidation And Reduction (JAMB)

Acids, Bases And Salts

Oxidation And Reduction

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Question 8 Report

When sodium nitrate dissolves in water, ∆H is positive. This means that?

the reaction is catalysed

the reaction is complete

the reaction is exothermic

the reaction is endthermic Correct answer

sodium nitrate is highly soluble in water

Answer Details

Read lesson note on Energy Changes (JAMB)

Energy Changes

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Question 9 Report

5cm³ of a saturated solution of sodium chloride at 30°C gave, on careful evaporation, 1.95g of solid salt. The solubility of sodium chloride at 30°C?

(Na = 23, Cl = 35.5)

5.00 mole dm³

5.67 mole dm³

6.00 mole dm³

6.67 mole dm³ Correct answer

7.00 mole dm³

Answer Details

Read lesson note on Solubility (JAMB)

Solubility

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Question 10 Report

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 Correct answer

Answer Details

Read lesson note on Acids, Bases And Salts (JAMB)

Acids, Bases And Salts

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Question 11 Report

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 Correct answer

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

Answer Details

Read lesson note on Kinetic Theory Of Matter And Gas Laws (JAMB)

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Question 12 Report

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

heating the acid

bubbling air through the acid Correct answer

cooling the acid

adding a decolorizing agent

adding a base

Answer Details

Read lesson note on Acids, Bases And Salts (Ghana Only) (WAEC)

Acids, Bases And Salts (Ghana Only)

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Question 13 Report

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 Correct answer

500 g

10 g

20 g

Answer Details

Read lesson note on Stoichiometry And Chemical Reactions (WAEC)

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Question 14 Report

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 Correct answer

1.0 x 10²²

5.4 x 10²³

Answer Details

Read lesson note on Kinetic Theory Of Matter And Gas Laws (JAMB)

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Question 15 Report

For iron to rust, there should be present?

oxygen

moisture

carbondioxide

oxygen and moisture Correct answer

oxygen, moisture and carbondioxide

Answer Details

Read lesson note on Energy And Energy Changes (WAEC)

Energy And Energy Changes

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Question 16 Report

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

a reducing agent

a nitrating agent

an oxidizing agent Correct answer

a catalytic agent

a neutralizing agent

Answer Details

Read lesson note on Oxidation And Reduction (JAMB)

Oxidation And Reduction

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Question 17 Report

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 Correct answer

100.1 dm³

3.0 dm³

22.4 dm³

Answer Details

Read lesson note on Stoichiometry And Chemical Reactions (WAEC)

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Question 18 Report

Allotropes are elements having?

different physical but the same chemical properties Correct answer

different chemical but the same physical properties

the same chemical and physical properties

different atomic structure

the same position in the periodic table

Answer Details

Read lesson note on Chemical Equilibria (JAMB)

Chemical Equilibria

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Question 19 Report

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

CaO Correct answer

CaCI₂

Conc. H₂SO₄

P₂O₅

H₃PO₄

Answer Details

Read lesson note on Acids, Bases And Salts (JAMB)

Acids, Bases And Salts

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Question 20 Report

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 Correct answer

calcium hydroxide

magnesium sulphate

Answer Details

Read lesson note on Solubility Of Substances (Ghana Only) (WAEC)

Read lesson note on Water (JAMB)

Solubility Of Substances (Ghana Only)

Water

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Question 21 Report

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 Correct answer

Nothing happens

Answer Details

Read lesson note on Electrolysis (JAMB)

Electrolysis

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Question 22 Report

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 Correct answer

31.7 cm³

Answer Details

Read lesson note on Kinetic Theory Of Matter And Gas Laws (JAMB)

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Question 23 Report

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 Correct answer

Answer Details

Read lesson note on Atomic Structure And Bonding (JAMB)

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Question 24 Report

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

Ice

Sulphur

Phosphurous

Iodine Correct answer

Potassium iodie

Answer Details

Read lesson note on Kinetic Theory Of Matter And Gas Laws (JAMB)

Read lesson note on Non-metals And Their Compounds (JAMB)

Non-metals And Their Compounds

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Question 25 Report

Which of the following can have an isomer?

C₂H₄

C₄H₁₀ Correct answer

C₃H₈

C₂H₆

C₆H₆

Answer Details

Read lesson note on Acids, Bases And Salts (JAMB)

Acids, Bases And Salts

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Question 26 Report

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 Correct answer

absorbs water from the air and dissolves in it

gives out its water of crystallization on heating

Answer Details

Read lesson note on Kinetic Theory Of Matter And Gas Laws (JAMB)

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Question 27 Report

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 Correct answer

3.00

3.66

4.00

Answer Details

Read lesson note on Kinetic Theory Of Matter And Gas Laws (JAMB)

Read lesson note on Stoichiometry And Chemical Reactions (WAEC)

Read lesson note on Acids, Bases And Salts (Ghana Only) (WAEC)

Acids, Bases And Salts (Ghana Only)

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Question 28 Report

Oxidation is the process of?

gain of electrons

loss of electrons Correct answer

gain of hydrogen

loss of oxygen

addition of an electropositive element to a substance

Answer Details

Read lesson note on Oxidation And Reduction (JAMB)

Oxidation And Reduction

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Question 29 Report

The general formula of an alkyl halide (which represent the halide) is?

C_nH_2n - ₂X

C_nH_2n + ₁X Correct answer

C_nH_2n + ₂X

C_nH_2nX

C_nH_2n - 1

Answer Details

Read lesson note on Chemistry Of Carbon Compounds (Nigeria Only) (WAEC)

Chemistry Of Carbon Compounds (Nigeria Only)

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Question 30 Report

When air is compressed?

its density decreases

it solidifies

its temperature decreases Correct answer

its temperature increases

its temperature remains unchanged

Answer Details

Read lesson note on Kinetic Theory Of Matter And Gas Laws (JAMB)

Read lesson note on Separation Of Mixtures And Purification Of Chemical Substances (JAMB)

Separation Of Mixtures And Purification Of Chemical Substances

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Question 31 Report

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 Correct answer

They conduct electricity

Answer Details

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Question 32 Report

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 Correct answer

Answer Details

Read lesson note on Chemical Bonds (Nigeria Only) (WAEC)

Chemical Bonds (Nigeria Only)

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Question 33 Report

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 Correct answer

Answer Details

Read lesson note on Acids, Bases And Salts (JAMB)

Acids, Bases And Salts

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Question 34 Report

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 Correct answer

Fe₂O₃ + 3C → 2Fe + 3CO₂

CaCO₃ → CaO + CO₂

CaO + SiO₂ → CaSiO₃

Answer Details

Read lesson note on Chemical Combination (JAMB)

Chemical Combination

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Question 35 Report

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 Correct answer

CuO +2HCl \(\to\) Cl₂ + H₂O

Answer Details

Read lesson note on Kinetic Theory Of Matter And Gas Laws (JAMB)

Read lesson note on Stoichiometry And Chemical Reactions (WAEC)

Read lesson note on Acids, Bases And Salts (Ghana Only) (WAEC)

Acids, Bases And Salts (Ghana Only)

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Question 36 Report

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 Correct answer

Na₂SO₄ + SO₃ + S + H₂O

Na₂SO₄ + SO₂ + H₂O only

Answer Details

Read lesson note on Acids, Bases And Salts (JAMB)

Acids, Bases And Salts

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Question 37 Report

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 Correct answer

None of the compounds is gaseous at 20 °C

Answer Details

Read lesson note on Kinetic Theory Of Matter And Gas Laws (JAMB)

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Question 38 Report

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

the atomic number

the avogadro number Correct answer

the gas constant

the number of neutrons

the number of electrons

Answer Details

Read lesson note on Structure Of The Atom (WAEC)

Structure Of The Atom

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Question 39 Report

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 Correct answer

Zinc

Answer Details

Read lesson note on Metals And Their Compounds (JAMB)

Read lesson note on Non-metals And Their Compounds (JAMB)

Metals And Their Compounds

Non-metals And Their Compounds

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Question 40 Report

The IUPAC name for

1-methlpentane

3-methylbutane

2-methylbutane Correct answer

1-dimethylpropane

2-methylpentane

Answer Details

Read lesson note on Chemistry Of Carbon Compounds (Nigeria Only) (WAEC)

Chemistry Of Carbon Compounds (Nigeria Only)

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Question 41 Report

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 Correct answer

576,000

Answer Details

Read lesson note on Electrolysis (JAMB)

Read lesson note on Stoichiometry And Chemical Reactions (WAEC)

Electrolysis