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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 261

jamb 2019

The combustion of carbon(II)oxide in oxygen can be represented by equation:
2CO + O\(_2\) → 2CO\(_2\)
Calculate the volume of the resulting mixture at the end of the reaction, if 50cm\(^3\) of carbon(ii)oxide was exploded in 100cm\(^3\) of oxygen

A75cm\(^3\)

B125cm\(^3\)

C100cm\(^3\)

D50cm\(^3\)

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Question 262

jamb 2019

By what amount must the temperature of 200cm\(^3\) of Nitrogen at 27°C be increased to double the pressure if the final volume is 150cm\(^3\) (Assume ideality)

A150°C

B177°C

C75°C

D120°C

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Question 263

jamb 2019

Elements X and Y have electronic configurations 1s\(^2\)2s\(^2\)2p\(^4\) and 1s\(^2\)2s\(^2\)2p\(^6\)3s\(^2\)3p\(^1\) respectively. When they combine, the formula of the compound formed is

AXY

BX\(_2\)Y

CY\(_2\)X\(_3\)

DX\(_2\)Y\(_3\)

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Question 264

jamb 2019

Which of the following statements does not show Rutherford's account of Nuclear Theory? An atom contains a region

Awhich contains protons and neutrons

Bwhich is positively charged

Cwhich is massive and can cause deflection of a few projectiles

Dwhich is very large and in which close to 98% of projectiles pass undeflected

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Question 265

jamb 2019

SO\(_3\) is not directly dissolved in water in the industrial preparation of H\(_2\)SO\(_4\) by the contact process because

ASO\(_3\) is an acidic gas

BAcid is usually added to water and not water to acid

CThe reaction between SO\(_3\) and water is violently exothermic

DSO\(_3\) does not dissolve readily in water

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Question 266

jamb 2019

Which of the following is a set of neutral oxides?

AN\(_2\)O, H\(_2\)O, CO

BN\(_2\)O, SO\(_2\), CO

CN\(_2\)O, Na\(_2\)O, ZnO

DN\(_2\)O, SO\(_3\), NO

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Question 267

jamb 2019

Which process(es) is/are involved in the turning of starch iodide paper blue-black by chlorine gas?

Achlorine attacks the starch to give the blue-black color

Bchlorine attacks the iodide ion to give the blue-black color

Cchlorine oxidizes the iodide ion to produce iodine which attacks the starch to give the blue-black color

Diodine attacks the starch to give the blue-black color

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Question 268

jamb 2019

When chlorine water is exposed to bright sunlight, the following products are formed

AHCl\(_{(aq)}\) and Cl\(_2\)

BHOCl\(_{(aq)}\) and Cl\(_2\)

CHCl\(_{(aq)}\) and O\(_2\)

DHOCl\(_{(aq)}\) and O\(_2\)

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Question 269

jamb 2019

Which of the following alkaline earth metals react more spontaneously with water?

ACalcium

BBeryllium

CMagnesium

DStrontium

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Question 270

jamb 2019

Which of the following metals is the most essential in the regulation of blood volume, blood pressure and osmotic equilibrium?

AZinc

BManganese

CSodium

DIron

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Question 271

jamb 2019

Which of the following is the best starting material for the preparation of oxygen? Heating of trioxonitrate (v) with

APb

BZn

CCa

DNa

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Question 272

jamb 2019

Burning magnesium ribbon in air removes which of the following
(i) oxygen (ii) nitrogen (iii) argon and (iv) carbon(iv)oxide?

Ai and iv only

Bi, ii, iii and iv only

Ci only

Di and ii only

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Question 273

jamb 2019

A synthetic rubber is not obtained from the polymerization of?

Aneoprene

Bisoprene

Cbutandiene

Dhexane

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Question 274

jamb 2019

The IUPAC name of the compound CF\(_3\)CHBrCl is

A2-chloro-2-bromo-1,1,1-trifluoroethane

B2-bromo-2-chloro-1,1,1-trifluoroethane

C1-bromo-1-chloro-2,2,2-trifluoroethane

D1,1,1-trifluoro-2-bromo-2-chloroethane

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Question 275

jamb 2019

Hydrocarbons which will react with Tollen's reagent conform to the general formula

AC\(_n\)H\(_{2n}\)

BC\(_n\)H\(_{2n + 2}\)

CC\(_n\)H\(_{2n - 2}\)

DC\(_n\)H\(_{2n + 1}\)OH

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Question 276

jamb 2019

2-methylprop-1-ene is an isomer of?

A3-methyl but-1-ene

B2-methyl but-1-ene

Cbut-2-ene

Dpent-2-ene

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Question 277

jamb 2019

A certain hydrocarbon on complete combustion at s.t.p produced 89.6dm\(^3\) of CO\(_2\) and 54g of water. The hydrocarbon should be?

AC\(_6\)H\(_6\)

BC\(_4\)H\(_{10}\)

CC\(_5\)H\(_{10}\)

DC\(_4\)H\(_6\)

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Question 278

jamb 2019

The IUPAC name for CH\(_3\)CH\(_2\)COOCH\(_2\)CH\(_3\) is

Amethylpropanoate

Bethylethanoate

Cethylpropanoate

Dmethylethanoate

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Question 279

jamb 2019

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

ABut-2-ene

BBut-1-ene

CBut-2-yne

DBut-1-yne

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Question 280

jamb 2019

A secondary alkanol can be oxidized to give an?

Aalkanone

Balkyne

Calkanoic acid

Dalkanal

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