JAMB UTME - Chemistry - 1981

Ver Resposta

Pergunta 8 Relatório

For iron to rust, there should be present?

oxygen

moisture

carbondioxide

oxygen and moisture

oxygen, moisture and carbondioxide

Detalhes da Resposta

Read lesson note on Energy And Energy Changes (WAEC)

Energy And Energy Changes

Ver Resposta

Pergunta 9 Relatório

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

Detalhes da Resposta

Read lesson note on Energy Changes (JAMB)

Energy Changes

Ver Resposta

Pergunta 10 Relatório

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

Detalhes da Resposta

Ver Resposta

Pergunta 11 Relatório

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

Detalhes da Resposta

Read lesson note on Stoichiometry And Chemical Reactions (WAEC)

Ver Resposta

Pergunta 12 Relatório

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

Detalhes da Resposta

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

Ver Resposta

Pergunta 13 Relatório

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

absorbs water from the air and dissolves in it

gives out its water of crystallization on heating

Detalhes da Resposta

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

Ver Resposta

Pergunta 14 Relatório

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

Detalhes da Resposta

Read lesson note on Chemical Combination (JAMB)

Chemical Combination

Ver Resposta

Pergunta 15 Relatório

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

Detalhes da Resposta

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)

Ver Resposta

Pergunta 16 Relatório

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

CaO

CaCI₂

Conc. H₂SO₄

P₂O₅

H₃PO₄

Detalhes da Resposta

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

Acids, Bases And Salts

Ver Resposta

Pergunta 17 Relatório

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

Detalhes da Resposta

Read lesson note on Electrolysis (JAMB)

Electrolysis

Ver Resposta

Pergunta 18 Relatório

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

Ice

Sulphur

Phosphurous

Iodine

Potassium iodie

Detalhes da Resposta

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

Ver Resposta

Pergunta 19 Relatório

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

Detalhes da Resposta

Read lesson note on Electrolysis (JAMB)

Read lesson note on Stoichiometry And Chemical Reactions (WAEC)

Electrolysis

Ver Resposta

Pergunta 20 Relatório

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

Detalhes da Resposta

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

Ver Resposta

Pergunta 21 Relatório

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

Detalhes da Resposta

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

Acids, Bases And Salts

Ver Resposta

Pergunta 22 Relatório

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

Detalhes da Resposta

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)

Ver Resposta

Pergunta 23 Relatório

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

Detalhes da Resposta

Read lesson note on Atomic Structure And Bonding (JAMB)

Ver Resposta

Pergunta 24 Relatório

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

209

105

Detalhes da Resposta

Read lesson note on Atomic Structure And Bonding (JAMB)

Ver Resposta

Pergunta 25 Relatório

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

Detalhes da Resposta

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

Ver Resposta

Pergunta 26 Relatório

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

Detalhes da Resposta

Read lesson note on Oxidation And Reduction (JAMB)

Oxidation And Reduction

Ver Resposta

Pergunta 27 Relatório

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

Detalhes da Resposta

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

Chemical Bonds (Nigeria Only)

Ver Resposta

Pergunta 28 Relatório

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

Detalhes da Resposta

Read lesson note on Stoichiometry And Chemical Reactions (WAEC)

Ver Resposta

Pergunta 29 Relatório

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

saturated

supersaturated

unsaturated

a solid

protonated

Detalhes da Resposta

Read lesson note on Electrolysis (JAMB)

Electrolysis

Ver Resposta

Pergunta 30 Relatório

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

Detalhes da Resposta

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

Read lesson note on Oxidation And Reduction (JAMB)

Acids, Bases And Salts

Oxidation And Reduction

Ver Resposta

Pergunta 31 Relatório

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

Detalhes da Resposta

Read lesson note on Atomic Structure And Bonding (JAMB)

Ver Resposta

Pergunta 32 Relatório

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

Detalhes da Resposta

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

Ver Resposta

Pergunta 33 Relatório

The oxidation number of manganese in KMnO₄ is?

Detalhes da Resposta

Read lesson note on Oxidation And Reduction (JAMB)

Oxidation And Reduction

Ver Resposta

Pergunta 34 Relatório

When air is compressed?

its density decreases

it solidifies

its temperature decreases

its temperature increases

its temperature remains unchanged

Detalhes da Resposta

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

Ver Resposta

Pergunta 35 Relatório

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

Detalhes da Resposta

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

Chemistry Of Carbon Compounds (Nigeria Only)

Ver Resposta

Pergunta 36 Relatório

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

Zinc

Detalhes da Resposta

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

Ver Resposta

Pergunta 37 Relatório

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

Detalhes da Resposta

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