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Chemistry Past Questions

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34 questions JAMB 2505 WAEC 1623 NECO 168 CUSTOM 10

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34 questions

Question 1 of 14 34 total questions

Question 11

jamb 1987

Ethanol reacts with aqueous sodium mono-oxoio date (l) to give a bright yellow solid with a characteristic smell. The product is?

Atrichloromethane

Btriodomethane

Ciodoethane

Dethanal

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Question 12

jamb 1987

The efficiency of petrol as a fuel in high-compression internal combustion engines improves with an increase in the amount of?

Abranched chain alkanes

Bstraight chain alkanes

Ccycloalkanes

Dhalogenated hydrocarbons

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Question 13

jamb 1987

Which of the following compounds will give a precipitate with an aqueous ammoniacal solution of copper (l) chloride?

ACH₃ = CHCH₃

BCH₃ ≡ CCH₃

CHC = C-CH₂CH₃

DCH₂ = CH-CH = CH₂

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Question 14

jamb 1987

Inspite of the electronic configuration, 1s²2s²2p², carbon is tetraavalent because?

Athe electrons in both 2s and 2p orbitals have equal energy

Bthe electrons in both 2s and 2p orbitals are equivalent

Cboth the 2s and 2p orbitals hybridizes

Dthe six orbitals hybridize to four

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Question 15

jamb 1987

Corrosion is exhibited by?

Airon only

Belectropostive metals

Cmetals below hydrogen inthe electrochemical series

Dall metals

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Question 16

jamb 1987

Alloys are best prepared by?

Ahigh temperature weilding of the metals

Belectrolysis using the major metallic component as cathode

Creducing a mixture of the oxies of the elements

Dcooling a molten mixture of the necessary elements

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Question 17

jamb 1987

Stainless steel is an alloy of?

AIron, carbon and silver

Biron, carbon and lead

Ciron, carbon and chromium

Diron and carbon only

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Question 18

jamb 1987

Which of the following elements will form oxide which will dissolve both in dilute HNO₃ and NaOH solutions to form salts?

AAl

BMg

CAg

DMn

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Question 19

jamb 1987

When sodium hydroxide is heated with ammonium tetraoxosulphate (IV), the gas given off may be collected by?

Abubbling it through concentrated H₂SO₂

Bbubbling it through water and then passing it through calcium oxide

Cpassing it directly through calcium oxide

Dpassing it directly through calcium chloride

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Question 20

jamb 1987

Which of the following gases can best be used for demonstrating the fountain experiment?
i) Nitrogen (ii) Ammonia (iii) Nitrogen (I) oxide
(iv) Hydrogen chloride.

Aii and iii

Bi and iii

Cii and iv

Dii only

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Question 21

jamb 1987

In which of the following pairs of element is allotropy exhibited by each element?

APhosphorus and hydrogen

BOxygen and chlorine

CSulphur and nitrogen

DOxygen and sulphur

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Question 22

jamb 1987

The best treatment for a student who accidentally poured concentrated tetraoxosulphate (VI) acid on his skin in the laboratory is to wash the skin with?

Acold water

Bsodium hydroxide solution

Ciodine solution

Dsodium trioxocarbonate (IV) solution

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Question 23

jamb 1987

Magnesium ribbon was allowed to burn inside a given gas P leaving a white solid residue Q. Addition of water to Q liberated a gas which produced dense white fumes with a drop of hydrochloric acid. The gas P was?

Anitrogen

Bchlorine

Coxygen

Dsulphur (IV) oxide

View Explanation & Discuss

Question 24

jamb 1987

The reaction between sulphur (IV) oxide and oxygen is represented by the equilibrium reaction 2SO_2(g) + O_2(g) ↔ 2SO_3(g), ∆H = -196 kJ. What factor would influence increased production of SO_3(g)?

AAddition of a suitable catalyst

BIncrease in the temperature of the reaction

CDecrease in the temperature of the reaction

DDecrease in the concentration of SO_2(g)

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