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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 331

jamb 2017

A sample of orange juice is found to have a PH of 3.80. What is the concentration of the hydroxide ion in the juice?

A1.6 \(\times\) 10^-4

B6.3 \(\times\) 10^-11

C6.3 \(\times\) 10^-4

D1.6 \(\times\) 10^-11

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Question 332

jamb 2017

When few drops of concentrated trioxonitrate(V) acid is added to an unknown sample and wanned an intense yellow colouration is observed. The likely functional group present in the sample is

ANH₂RCHCOOH

BCHO

CCO

DCNH₂

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Question 333

jamb 2017

An isomer of C₅H₁₂ is

A2–ethyl butane

Bbutane

C2–methyl butane

D2–methyl propane

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Question 334

jamb 2017

The oxidation number of iodine in KIO₃ is

A+7

B+3

C+5

D+6

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Question 335

jamb 2017

A given mass of gas occupies 2dm³ at 300k. At what temperature will its volume be doubled, keeping the pressure constant?

A400k

B480k

C550k

D600k

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Question 336

jamb 2017

For a general equation of the nature xP + yQ → mR + nS, the expression for the equilibrium constant is

Ak [P]^x [Q]^y

B\(\frac{[P]^x [Q]^y}{[R]^m [S]^n}\)

C\(\frac{[R]^m [S]^n}{[P]^x [Q]^y}\)

D\(\frac{m[R] n[S]}{x[P] y[Q] }\)

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Question 337

jamb 2017

The constituent of air necessary in the rusting process are

AO₂ and H₂O

BAr and CO₂

CCO₂ and H₂O

DO₂ and CO₂

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Question 338

jamb 2017

In the laboratory preparation of ethyl ethanoate, the water present in the mixture is removed using ?

AAnhydrous CaCl₂

Bconcentrated NaCO₄

Cdilute NaOH

Dconcentrated H₂SO₄

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Question 339

jamb 2017

The process that occurs when two equivalent forms of a compound are in equilibrium is

AIsotopy

BResonance

CIsomerism

DReforming

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Question 340

jamb 2017

The acid anhydride that will produce weak acid in water is

ASO₃

BNO₂

CSO₂

DCO₂

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Question 341

jamb 2017

Temporary hard water is formed when rain water containing dissolved carbon(IV) oxide flows over deposits of

ACaCO₃

BNa₂CO₃

CNa₂SO₄

DCaSO₄

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Question 342

jamb 2017

The tincture of iodine means iodine dissolved in

Aethanol

Bbromine chloride

Cchlorine water

Dwater

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Question 343

jamb 2017

Aluminium hydroxide is used in the dyeing industry as a

Adye

Bdispersant

Csalt

Dmordant

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Question 344

jamb 2017

The shape of the S-orbital is

Aelliptical

Bspiral

Ccircular

Dspherical

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Question 345

jamb 2017

The constituent common to duralumin and alnico is

ACo

BMn

CAl

DMg

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Question 346

jamb 2017

The general formula of alkanones is

ARCHO

BRCOR'

CRCOOH

DRCOOR

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Question 347

jamb 2016

N₂O_4(aq) \(\rightleftharpoons\) 2NO_2(g) \(\bigtriangleup\)H = +ve

In the reaction above, an increase in temperature will

AIncrease the reactant production

BIncrease the value of the equilibrium constant

CShift the equilibrium to the left

DDecrease the value of the equilibrium constant

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Question 348

jamb 2016

CH_4(g) + CI_2(g) \(\to\) CH₂CI_(s) + HCI_g

The major factor that influences the rate of the reaction above is

AConcentration

BCatalyst

CTemperature

DLight

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Question 349

jamb 2016

From the diagram above, an ideal gas can be represented by

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Question 350

jamb 2016

The curve depicts titration between a strong acid of pH

AStrong acid and strong base

BStrong acid and weak base

CWeak acid and weak base

DWeak acid and strong base

View Explanation & Discuss

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