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Chemistry Past Questions

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49 questions JAMB 2505 WAEC 1623 NECO 168 CUSTOM 10

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Past Questions

49 questions

Question 1 of 20 49 total questions

Question 1

jamb 1989

CO(g) + H\(_2\)O(g) \(\to\) \(CO_{2g}\) + H\(_2\)(g) \(\Delta\)H = - 4100J. Which of the following factors favour the formation of hydrogen in the above reaction? i. high pressure. ii. low pressure iii. high-temperature iv. use of excess steam

Ai, iii and iv

Biii only

Cii, iii and i

Div only

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Question 2

jamb 1989

What is the IUPAC name for the compound

A1-chloro-2-methylprop-2,3-ene

B1-chloro-2-methylprop-2-ene

C3-chloro-2-methylprop-1-ene

D3-chloro-2methylprop-1,2-ene

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Question 3

jamb 1989

Use the figure above to answer this question. Which of the following is NOT an isomer of the compound?

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Question 4

jamb 1989

Use the figure above to answer this question. Which of the following compounds is an isomer of the compound

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Question 5

jamb 1989

The above graph shows a typical heating curve from the solid phase through the liquid phase to the gaseous phase of a substance. Which part of the curve shows solid and liquid in equilibrium?

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Question 6

jamb 1989

If in the graph above 1 dm 3 of a saturated solution of KCL is cooled from 80°C, the mass of crystals deposited will be
[K = 39, Cl = 35.5]

A7.45 g

B14.90 g

C74.50 g

D149.00 g

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Question 7

jamb 1989

The above diagram gives the potential energy profile of the catalyst and uncatalysed reactions of X(g) + Y(g) → XY(g). Deduce the respective activation energies in KJ of the catalysed and uncatalysed reverse reactions: XY(g) → X(g) + Y(g)

A300, 500

B500, 300

C-300, -500

D-500, -300

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Question 8

jamb 1989

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

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Question 9

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 10

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 11

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 12

jamb 1989

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

Abutane

Bethene

Cethane

Dmethane

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Question 13

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 14

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 15

jamb 1989

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

Aesterification

Bneutralization

Chydroxylation

Dhydrolysis

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Question 16

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 17

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 18

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 19

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 20

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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