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Chemistry Past Questions

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2,505 questions JAMB 2505 WAEC 1623 NECO 168 CUSTOM 10

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2,505 questions

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Question 711

jamb 2001

\(C_{12}H_{22}O_{11(s)} + H_2SO_{4(aq)} → 12C(s) + 11H_2O(l) + H_2SO_{4(aq)}\)
In the reaction above, tetraoxosulphate (VI) acid function as

AA dehydrating agent

BAn oxidizing agent

CA reducing agent

DA catalyst

View Explanation & Discuss

Question 712

jamb 2001

Which of the following represent hybridization in ethyne?

ASp²

BSp²d

CSp³

DSp

View Explanation & Discuss

Question 713

jamb 2001

Which of the following metals burn with brick red flame?

APb

BCa

CNa

DMg

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Question 714

jamb 2001

The gas that can best be collected by downward displacement of air is

AChlorine

BSulphur (IV) oxide

CAmmonia

DCarbon (IV) oxide

View Explanation & Discuss

Question 715

jamb 2001

A burning candle produces water and

ACarbon (II) oxide

BCarbon (IV) oxide

COxygen

DHydrogen

View Explanation & Discuss

Question 716

jamb 2001

The pair of organic compounds that are isomers is

ABenzene and methylbenzene

BTrichloromethane and tetrachloromethane

CEthanol and propane

DBut-1-ene and but-2-ene

View Explanation & Discuss

Question 717

jamb 2001

A characteristic reaction of the compounds with the general formula C\(_n\)H\(_{2n}\) is

AEsterification

BPolymerization

CDecarboxylation

DSubstitution

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Question 718

jamb 2001

Proteins in acid solution undergo

APolymerization

BSubstitution

CFermentation

DHydrolysis

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Question 719

jamb 2001

When chlorine Is passed into water and the resulting solution exposed to sunlight, the product formed are

AChlorine gas and hydrogen

BOxygen and oxochlorate (I) acid

CChlorine gas and oxochlorate (I) acid

DHydrochloric acid and oxygen

View Explanation & Discuss

Question 720

jamb 2001

A trihydric alkanol is

AGlycerol

BPhenol

CGlycol

DEthanol

View Explanation & Discuss

Question 721

jamb 2001

Catalytic hydrogenation of benzene produces

AOil

BCyclohexene

CCyclohexane

DMargarine

View Explanation & Discuss

Question 722

jamb 2001

During the vulcanization of rubber, sulphur is added to

ABreak down rubber polymer

BLengthen the chain of rubber

CBind rubber molecules together

DAct as a catalyst

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Question 723

jamb 2001

The main impurity in iron ore during the extraction of iron is

ASilicon (IV) oxide

BCarbon (IV) oxide

CCalcium trioxosilicate

DSulphur (II) oxide

View Explanation & Discuss

Question 724

jamb 2001

The general formula for the alkanals is

AROH

BR₂CO

CRCOOR¹

DRCHO

View Explanation & Discuss

Question 725

jamb 2001

Fermentation is the

Abreaking down of carbohydrate to glucose

Bconversion of sugar to alcohol in the presence of yeast

Cbreaking down of sugar to carbohydrate

Dconversion of alcohol to sugar in the presence of yeast

View Explanation & Discuss

Question 726

jamb 2001

NH\(_3\)\(_{(g)}\) + HCl\(_{(g)}\) → NH\(_4\)Cl\(_{(s)}\)
The entropy change in the system above is

Anegative

Bindeterminate

Cpositive

Dzero

View Explanation & Discuss

Question 727

jamb 2001

In which of the following reactions has the oxidation number of nitrogen increased?

A2NO_(g) + Br_2(l) → 2NOBr_(l)

B2NO_(g) + O_2(g) → 2NO_2(g)

CFeSO_4(aq) + NO_(g) → Fe(NO)SO_4(s)

D2NO(g) + Cl_2(g) → 2NOCl(l)

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Question 728

jamb 2001

As the concentration of an electrolyte reduces, the conductivity

Areduces to zero

Bdecreases

Cincreases

Dis unaffected

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Question 729

jamb 2001

When ΔH is negative, a reaction is said to be

Aionic

Breversible

Cexothermic

Dendothermic

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Question 730

jamb 2001

3Cu(s) + 8HNO\(_3\)(aq) → 3Cu(NO\(_3\))\(_2\)(aq) + 4H\(_2\)O(l) + 2NO(g)
In the equation above, copper is

Aan electron acceptor

Ba base

Can oxidizing agent

Da reducing agent

View Explanation & Discuss

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