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Chemistry Past Questions

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82 questions JAMB 2505 WAEC 1623 NECO 168 CUSTOM 10

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82 questions

Question 1 of 20 82 total questions

Question 21

jamb 1989

Which of the curves in the above graph illustrates the behaviour of an ideal gas?

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Question 22

jamb 1989

In the above set up substances X and Y are respectively

Alime water copper (ll) tetraoxosulphate (lV)

Bpotassium trioxocarbonate and alkaline pyrogallol

Cpotassium hydroxide and alkaline pyrogallol

Dpotassium trioxocarbonate (lV) and concentrated tetraoxosulphate (IV) acid

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Question 23

jamb 1989

It can be deduced from the vapour pressure curves above that

Aliqiud 1 has the highest boiling point

Bliquid ll has the highest boiling point

Cliquid lll has the highest boiling point

Dliquid lll has the lowest boiling point

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Question 24

jamb 1989

Three liquids X, Y and Z containing only hydrogen and carbon were burnt on a spoon. X and Y burnt with sooty flames while Z did not. Y is able to discharge the colour of bromine water whereas X and Z cannot. Which of the liquids would be aromatic in nature?

AX and Z

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Question 25

jamb 1989

The gas responsible for most of the fatal explosions in coal mines is

Abutane

Bethene

Cethane

Dmethane

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Question 26

jamb 1989

The alkaline hydrolysis of fats and oils produces soap and

Apropane 1, 1, 3 - triol

Bpropane - 1,2,3 - triol

Cpropane - 1,3,3 - triol

Dpropane - 1, 2, 2 - triol

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Question 27

jamb 1989

The bond which joins two ethanoic acid molecules in the liquid state is

Aa covalent bond

Ban ionic bond

Ca dative covalent bond

Da hydrogen bond

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Question 28

jamb 1989

The reaction between ethanoic acid and sodium hydroxide is an example of

Aesterification

Bneutralization

Chydroxylation

Dhydrolysis

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Question 29

jamb 1989

Vulcanization of rubber is a process by which

Aisoprene units are joined to produce rubber

Brubber latex is coagulated

Csulphur is chemically combined in the rubber

Dwater is removed from the rubber

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Question 30

jamb 1989

When excess chlorine is mixed with ethene at room temperature, the product is

A1,2 - dichloroethane

B1,2 - dichloroethene

C1,1 - dichloroethane

D1, 1 - dichloroethene

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Question 31

jamb 1989

Which of the following is NOT involved in the extraction of metals from their ores?

Areduction with carbon

Breduction with other metals

Creduction by electrolysis

Doxidation with oxidizing agents

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Question 32

jamb 1989

Mortar is NOT used for under-water construction because

Ait hardens by lose of water

Bits hardening doe not depend upon evaporation

Cit requires concrete to harden

Dit will be washed away by the flow of water

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Question 33

jamb 1989

A metal is extracted from its ore by the electrolysis of its molten chloride and it displaces lead from lead (ll) trioxonitrate (V) solution. The metal is

Acopper

Baluminium

Czinc

Dsodium

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Question 34

jamb 1989

The scale of a chemical balance is made of iron plate and coated with copper electrolytically because

Airon is less susceptible to corrosion than copper

Bcopper is twice as less susceptitible to corrosion as iron

Ccopper is less susceptible to corrosion than iron

Dcopper and iron are equally susceptible to corrosion

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Question 35

jamb 1989

The products of the thermal decomposition of ammonium trioxonitrate (V) are

ANO ₂ and oxygen

BNH₃ and oxygen

Cnitrogen and water

DN₂O and water

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Question 36

jamb 1989

Bleaching powder, CaOCI₂, H₂O, deteriorates on exposure to air because

Ait loses its water of crystallization

Batmospheric nitrogen displaces chlorine from it

Ccarbon (IV) oxide of the atmosphere displaceschlorine from it

Dbleaching agents should be stored in solution

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Question 37

jamb 1989

Which of the following reactions is (are) feasible?
I Br (l) + 2CI\(_2\)(aq) → 2Br(aq) + CI\(_2\)(g)
ll 2 I (aq) + Br\(_2\)(L) → 2Br (aq) + I\(_2\)(s)
lll 2F (aq) + CI\(_2\)(g) → 2CI (aq) + F\(_2\)(g)

IV 2F(aq) + Br\(_2\)(l) → 2Br (aq) + F\(_2\)(g)

Bll

Cl and lll

Dlll and lV

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Question 38

jamb 1989

Gunpower is made from charcoal, sulphur and potassium trioxonitrate (V) The salt in the mixture performs the function of

Aan oxidant

Ba reductant

Ca solvent

Da catalyst

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Question 39

jamb 1989

Some products of destructive distillation of coal are?

Acarbon (IV) oxide and ethanoic acid

Btrioxocarbonate (IV) acid and methanoic acid

Cproducer gas and water gas

Dcoke and ammoniacal liquor

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Question 40

jamb 1989

The catalyst used in the contact process for the manufacture of tetraoxosulphate (VI) acid is

Amanganes (IV) oxide

Bmanganese (ll) tetraoxosulphate (VI)

Cvanadium (V) oxide

Diron metal

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