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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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4,306 questions

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Question 371

jamb 2020

An organic compound that does not undergo a reaction with both hydrogen cyanide and hydroxylamine can be?

AAlkene

BAlkanal

CAlkanone

DAlkanoic Acid

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Question 372

jamb 2020

Which of the following types of bonding does not involve the formation of new substances?

AMetallic

BCovalent

CCo-ordinate

DElectrovalent

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Question 373

jamb 2020

What quantity of electricity will liberate 0.125 mole of oxygen molecules during the electrolysis of dilute sodium chloride solution?

A24,125 C

B48,250 C

C72,375 C

D96,500 C

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Question 374

jamb 2020

A gaseous metallic chloride MCl consists of 20.22% of M by mass. The formula of the chloride is?

[ M = 27, Cl = 35.5]

AMCl

BMCl\(_2\)

CMCl\(_3\)

DM\(_2\)Cl\(_6\)

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Question 375

jamb 2020

32g of anhydrous copper(ii)tetraoxosulphate(vi) dissolved in 1dm\(^3\) of water generated 13.0kj of heat. The heat solution is?

A26.0kj/mol

B65.0kj/mol

C130.0kj/mol

D260.0kj/mol

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Question 376

jamb 2020

Helium is used in observation of ballons because it is?

ALight and combustible

Blight and non-combustible

Cheavy and combustible

Dheavy and non-combustible

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Question 377

jamb 2020

Deliquescent substances are also?

Aefflorescent

Banhydrous

Chygroscopic

Dinsoluble

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Question 378

jamb 2020

Chromatography is used to separate components of mixture which differ in their rates of ?

Adiffusion

Bmigration

Creaction

Dsedimentation

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Question 379

jamb 2020

A few drop of conc HCL are added to about 10cm\(^3\) of a solution of PH 3.4. The PH of the resulting mixture is?

Aless than 3.4

Bgreater than 3.4

Cunaltered

Dthe same as that of the pure water

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Question 380

jamb 2020

The shape of ammonia molecule is?

ATrigonal planar

BOctahedral

CSquare planar

DTetrahedral

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Question 381

jamb 2020

Which of the following gases will rekindle a brightly splint?

BNO

CN\(_2\)O

DCL\(_2\)

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Question 382

jamb 2020

The volume occupied by 1.58g of a gas at S.T.P is 500cm\(^3\). What is the relative molecular mass of the gas? [ G.M.V at S.T.P = 22.4dm\(^{3}\) ]

A28

B32

C44

D71

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Question 383

jamb 2020

The number of molecules of Carbon(iv)Oxide produced when 10.0g of CaCO\(_3\) is treated with 0.2dm\(^3\) of 1 Mole of HCL in the equation

CaCO\(_3\) + 2HCL ⇒ CaCl\(_2\) + H\(_2\) O + CO\(_2\) , is?

A1.00 X 10\(^{23}\)

B6.02 X 10\(^{23}\)

C6.02 X 10\(^{22}\)

D6.02 X 10\(^{24}\)

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Question 384

jamb 2020

How many valence electrons are contained in the element \(^{31}_{15}P\)?

C15

D31

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Question 385

jamb 2020

The products of the thermal decomposition of ammonium trioxonitrate(v) are?

ANitrogen (I) Oxide and Water

BAmmonia and Oxide

CNitrogen and Water

DNitrogen (IV) Oxide and Water

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Question 386

jamb 2020

Four elements P, Q, R and S have atomic numbers of 4, 10, 12 and 14 respectively. Which of these elements is noble gas?

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Question 387

jamb 2020

If the quantity of oxygen occupying 2.76L container at a pressure of 0.825 atm and 300k is reduced by one-half, what is the pressure exerted by the remaining gas?

A1.650atm

B0.825atm

C0.413atm

D0.275atm

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Question 388

jamb 2020

Which of the following substances is a mixture?

AGranulated sugar

BSeawater

CSodium chloride

DIron filling

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Question 389

jamb 2020

When water drops are added to calcium carbide in a container and the gas produced is passed through a jet and lighted, the resultant flame is called an?

AOxyethene

BOxyhydrocarbon flame

COxyacetylene flame

DOxymethane flame

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Question 390

jamb 2020

Liquid black soap is made by boiling palm oil with liquid extract of ash. The function of the ash is to provide the ?

AAcid

BEster of alkanoic acid

CAlkanol

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