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Chemistry Past Questions

Study and practice Chemistry past questions with answers and detailed explanations. Then test your knowledge using our interactive CBT practice platform and prepare confidently for your upcoming examinations.

90 questions JAMB 2505 WAEC 1623 NECO 168 CUSTOM 10

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Past Questions

90 questions

Question 1 of 20 90 total questions

Question 21

waec 2014

Which of the following arrangements is in decreasing order of atomic radius?

ALi>Be>C>

BLi>B>Be>C

CLi>Be>B>C

DC>B>Be>Li

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Question 22

waec 2014

The two elements ₁₁X and ₁₉Y are in the same group because they have the same

Avalence electrons

Bionization energy

Cnumber of shell

Datomic size

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Question 23

waec 2014

Hydrogen bonds are formed between molecules containing a hydrogen atom bonded to a

Astrongly electronegative atom

Bnon-polar species

Cdiatomic element

Dcomplex ion

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Question 24

waec 2014

The crystal layers in graphite are held together by

Acovalent bond

Belectrostatic forces

Cionic bond

Dvan der Waal's forces

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Question 25

waec 2014

The shape of CH₄ is

Alinear

Bplanar

Cpyramidal

Dtetrahedral

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Question 26

jamb 2014

Z in diagram above represents

Aheat of reaction

Bactivation energy

Cfree energy

Dentropy of reaction

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Question 27

jamb 2014

In the diagram, the function of the concentrated H2SO4 is to?

Apurify the gas

Bdry the gas

Cliquefty the gas

Dremove odour

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Question 28

jamb 2014

The IUPAC nomenclature of the compound above is

A2-bromo-3-chlorobutanol

B3-bromo-2-chlorobutanol

C3-chloro-2-bromobutanol

D2-chloro-3-bromobutanol

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Question 29

jamb 2014

The petroleum fraction that is used in heating furnaces in industries is

Adiesel oil

Bgasoline

Ckerosene

Dlubricating oil

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Question 30

jamb 2014

The process of converting linear alkanes to branched chain and cyclic hydrocarbons by heating in the presence of a catalyst to improve the quality of petrol is referred to as

Arefining

Bcracking

Creforming

Dblending

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Question 31

jamb 2014

Polystyrene is widely used as packaging materials for fragile objects during transportation because of its

Alightness

Blow density

Chigh density

Dhigh compressibility

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Question 32

jamb 2014

A hydrocarbon has an empirical formula CH and a vapour density of 39. Determine its molecular formula.

[C = 12, H = 1]

AC₂H₆

BC₃H₈

CC₃H₄

DC₆H₆

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Question 33

jamb 2014

CH3COOC2H5(1) + H2O(1) ⇌ CH 3COOH (aq) + C 2H 5OH (aq)

The purpose of H+ in the reaction above is to

Aincrease the yield of products

Bmaintain the solution at a constant PH

Cincrease the rate of the hydrolysis

Ddecrease the rate of the reverse reaction

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Question 34

jamb 2014

The polymer used in making car rear lights is

Aperspex

Bbakeelite

Cpolystyrene

Dpolyacrylonitrile

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Question 35

jamb 2014

The process of converting starch to ethanol is

Acracking

Bdistillation

Cfermentation

Doxidation

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Question 36

jamb 2014

Due to the unstable nature of ethyne, it is stored by dissolving in

Aethane-1,2-diol

Bpropanol

Cethanoic acid

Dpropanone

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Question 37

jamb 2014

Ethyne is passed through a hot tube containing organo-nickel catalyst to produce

Aisoprene

Bpolythene

Cethanol

Dbenzene

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Question 38

jamb 2014

The alkanol obtained from the production of soap is

Apropanol

Bethanol

Cglycerol

Dmethanol

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Question 39

jamb 2014

The general formula of haloalkanes where X represents the halide is

AC_n H _2n-1X.

BC _nH _2nX.

CC _nH _2n+2 X

DC _nH _2n+1X

View Explanation & Discuss

Question 40

jamb 2014

A few drops of NaOH solution was added to an unknown salt forming a white precipitate which is insoluble in excess solution. The cation likely present is

AZn²⁺

BPb²⁺

CCa²⁺

DAl³⁺

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