JAMB UTME - Chemistry - 1981

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Question 3 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

31.7 cm³

Answer Details

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

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Question 4 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

Nothing happens

Answer Details

Read lesson note on Electrolysis (JAMB)

Electrolysis

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Question 5 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

Answer Details

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

Chemical Bonds (Nigeria Only)

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Question 6 Report

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

heating the acid

bubbling air through the acid

cooling the acid

adding a decolorizing agent

adding a base

Answer Details

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

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Question 7 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

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 8 Report

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

Answer Details

Read lesson note on Chemical Combination (JAMB)

Chemical Combination

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Question 9 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

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 10 Report

Allotropes are elements having?

different physical but the same chemical properties

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 11 Report

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

C_nH_2n - ₂X

C_nH_2n + ₁X

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 12 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

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 13 Report

An example of a strong electrolyte is?

ethyl acetate

ethanol

glucose

sodium formate

formic acid

Answer Details

Read lesson note on Electrolysis (JAMB)

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

Electrolysis

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Question 14 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

dative covalent

metallic

none of the above

Answer Details

Read lesson note on Atomic Structure And Bonding (JAMB)

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Question 15 Report

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

209

105

Answer Details

Read lesson note on Atomic Structure And Bonding (JAMB)

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Question 16 Report

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

Answer Details

Read lesson note on Chemical Combination (JAMB)

Chemical Combination

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Question 17 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

sodium nitrate is highly soluble in water

Answer Details

Read lesson note on Energy Changes (JAMB)

Energy Changes

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Question 18 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

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 19 Report

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

saturated

supersaturated

unsaturated

a solid

protonated

Answer Details

Read lesson note on Electrolysis (JAMB)

Electrolysis

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Question 20 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

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 21 Report

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

Ice

Sulphur

Phosphurous

Iodine

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 22 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

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 23 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

1s² 2s²2p⁶ 3s^°

1s² 2s²2p⁶ 4s¹

Answer Details

Read lesson note on Atomic Structure And Bonding (JAMB)

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Question 24 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

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)

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Question 25 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

Answer Details

Read lesson note on Atomic Structure And Bonding (JAMB)

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Question 26 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

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 27 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

They conduct electricity

Answer Details

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Question 28 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

7.00 mole dm³

Answer Details

Read lesson note on Solubility (JAMB)

Solubility

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Question 29 Report

Oxidation is the process of?

gain of electrons

loss of electrons

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 30 Report

The oxidation number of manganese in KMnO₄ is?

Answer Details

Read lesson note on Oxidation And Reduction (JAMB)

Oxidation And Reduction

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Question 31 Report

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

Answer Details

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

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Question 32 Report

When air is compressed?

its density decreases

it solidifies

its temperature decreases

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 33 Report

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

condensation products of formaldehyde and glycerol

liquids at 20°C

Answer Details

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

Read lesson note on Chemistry, Industry And The Environment (WAEC)

Read lesson note on Metals And Their Compounds (JAMB)

Chemistry Of Carbon Compounds (Nigeria Only)

Chemistry, Industry And The Environment

Metals And Their Compounds

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Question 34 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

500 g

10 g

20 g

Answer Details

Read lesson note on Stoichiometry And Chemical Reactions (WAEC)

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Question 35 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

Answer Details

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

Acids, Bases And Salts

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Question 36 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

576,000

Answer Details

Read lesson note on Electrolysis (JAMB)

Read lesson note on Stoichiometry And Chemical Reactions (WAEC)

Electrolysis

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Question 37 Report

Methane is member of the homologous series called?

alkenes

alcohols

esters

alkanes

alkynes

Answer Details

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

Periodic Chemistry (Ghana Only)

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Question 38 Report

Which of the following can have an isomer?

C₂H₄

C₄H₁₀

C₃H₈

C₂H₆

C₆H₆

Answer Details

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

Acids, Bases And Salts

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Question 39 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

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 40 Report

For iron to rust, there should be present?

oxygen

moisture

carbondioxide

oxygen and moisture

oxygen, moisture and carbondioxide

Answer Details

Read lesson note on Energy And Energy Changes (WAEC)

Energy And Energy Changes

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Question 41 Report

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

a reducing agent

a nitrating agent

an oxidizing agent

a catalytic agent

a neutralizing agent

Answer Details

Read lesson note on Oxidation And Reduction (JAMB)

Oxidation And Reduction

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Question 42 Report

A polymerization reaction is one in which?

small molecules form giant molecules

atoms form molecules

giant molecules form small molecules

molecules form volatile compounds

a molecule rearranges itself

Answer Details

Read lesson note on Basic Biochemistry And Synthetic Polymers (WAEC)

Basic Biochemistry And Synthetic Polymers

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Question 43 Report

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

hydrogen

carbon monoxide

carbon dioxide

sulphur oxide

chlorine

Answer Details

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

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Question 44 Report

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

the atomic number

the avogadro number

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 45 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

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)