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Chemistry Past Questions

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4,306 questions JAMB 2505 WAEC 1623 NECO 168 CUSTOM 10

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Past Questions

4,306 questions

Question 1 of 20 4,306 total questions

Question 1881

waec 1988

Which of the following is a waste product in the Solvary Process for the manufacture of sodium trioxocarbonate (IV)?

AAmmonium chloride

BBrine

CLimestone

DCalcium oxide

ECalcium chloride

View Explanation & Discuss

Question 1882

waec 1988

Which of the following correctly explains why iodine crystals change directly into the gaseous state when heated?

Alodine crystals sublime

Blodine atoms are held together by strong forces

Clodine molecules are held together by weak forces

Dlodine molecules are covalent

Elodine is a solid at room temperature

View Explanation & Discuss

Question 1883

waec 1988

Aqueous sodium trioxocarbonate (IV) solution is alkaline because

Aacid from which it is formed is strong

Bsodium is an alkali metal

Csodium trioxocarbonate (IV) is decomposed by water

Dsodium trioxocarbonate (lV) is stable to heat

Esodium triocarbonate (IV) is hydrolysed in water

View Explanation & Discuss

Question 1884

waec 1988

Which of the following equations represents the reaction of chlorine with hot concentrated sodium hydroxide solution?

A2NaOH+CI₂ → NaCIO + NaCI + H₂O

B4NaOH + 2CI → 4NaCI + 2H₂O + O₂

C6NaOH + 3CI₂ → NaCIO₃ + 5NaCI + 3H₂O

D2NaOH + CI₂ → 2NaCI + H₂O₂

ENaOH + 2CI₂ + H₂O → NaCI + 3HCI + O₂

View Explanation & Discuss

Question 1885

waec 1988

Which of the following is not a naturally occurring iron ore?

AFeCl₂

BFe₃O₄

CFe₂O₃

DFeCO₃

EFeS₂

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Question 1886

waec 1988

Which of the following metals cannot extracted from its ore by using carbon (ll) oxide as the reducing agent?

ACu

BZn

CAl

DPb

EFe

View Explanation & Discuss

Question 1887

waec 1988

Water gas is a mixture of?

ACO_{2 and H₂}

BCO and H₂O

CCO₂ and CO

DCO and N₂

ECO and H₂

View Explanation & Discuss

Question 1888

waec 1988

How many isomers can be obtained from C_4H₁₀?

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Question 1889

waec 1988

What volume of oxygen will be left unreacted when a mixture of 100cm³ of hydrogen and 200cm,sup>3,/sup> of oxygen are exploded in a eudiometer?

A300cm³

B200cm³

C150cm³

D100cm³

E50cm³

View Explanation & Discuss

Question 1890

waec 1988

Which of the following is not true of the rusting of iron?

ARusting is a reduction process

BRusting of iron takes place in the presence of oxygen and moisture

Cthe rust formed is reddish brown

Dthe major constituent of rust is hydrated iron (lll) oxide

Erusting is similar to burning

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Question 1891

waec 1988

Which of the following is not true of the rusting of iron?

ARusting is a reduction process

BRusting of iron takes place in the presence of oxygen and moisture

Cthe rust formed is reddish brown

Dthe major constituent of rust is hydrated iron (lll) oxide

Erusting is similar to burning

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Question 1892

waec 1988

Which of the following is not decomposed by heat?

ACaCO₃

BCuCO₃

CZnCO,sub>3

DNa₂CO₃

EMgCO₃

View Explanation & Discuss

Question 1893

waec 1988

Bubbling of carbon (IV)oxide into calcium hydroxide solution results in the formation of

ACaCO₃

BCuCO₃

CZnCO₃

DNa₂CO₃

EMgCO₃

View Explanation & Discuss

Question 1894

waec 1988

What quantity of silver is deposited when 96500C of electricity is passed through a solution containing silver ions? (Ag = 108, 1F = 96500C)

A1.08g

B40g

C10,.8g

D21.6g

E108g

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Question 1895

waec 1988

The following are heavy chemicals except

Atetraoxosulphate (IV) acid

Bcaustic soda

Csodium trioxocarbonate (IV)

Dethene

Edyes

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Question 1896

waec 1988

The main characteristic feature of transition metals is that they

Ahave the same atomic size

Bare reducing agents

Cfrom ions easily

Dhave variable oxidation states

Eare highly electropositive

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Question 1897

waec 1988

The following are uses of radioactive isotopes except for

Asterilization of medical equipment

Btracing reaction paths

Cdating elements

Dradiography

Edetermining equilibrum positions

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Question 1898

waec 1988

Which of the following statements is not correct?

ACarbon exhibits allotropy

BSulphur exhibits allotropy

CChlorine exhibits allotopy

DNitrogen is a gas

EArgon is a noble gas

View Explanation & Discuss

Question 1899

waec 1988

Which of the following is a neutral oxide?

ANitrogen (IV0 oxide

BCarbon (IV) oxide

CSulphur (IV) oxide

DPhodphoorus (IV) oxide

ENitrogen oxide

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Question 1900

waec 1988

Which of the following types of hybridization gives rise to tetrahedral molecules?

Asp

Bsp²

Csp₃

Dsp³d

Esp³d²

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