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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

Question 1 of 20 4,306 total questions

Question 991

neco 2008

The rate of a chemical reaction is NOT affected by one of these factors

Acolour

Bconcentration

Cpresence of light

Dsurface area

Etemperature

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Question 992

neco 2008

The molecular formula of ethylbutanoate is?

ACH₅COOC₂6

BC₃HCOOC₂H₇

CC₃H₇COOC₃H₇

DC₃H₇COOC₄H₉

EC₃H₇COOC₂H₅

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Question 993

neco 2008

Which of the following is a component of the car exhaust?

AAluminium

BCalcium

CIron

DZinc

ELead

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Question 994

neco 2008

Which of the following will Increase the rate of reaction of Chips of a metal M as shown in the equation below?

M(s)+2HC1(aq) → MCI₂ (aq) + H₂(g)

AAdding some distilled water

BDecreasing the temperature

CDiluting the hydrochloric acid

DGrinding the metal into powder

EIncreasing the pressure

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Question 995

neco 2008

What is the colour of phenolphthalein indicator in a basic medium?

ABlue

BColourless

COrange

DPink

EYellow

View Explanation & Discuss

Question 996

neco 2008

\( ^{234}_{90}Th → ^{234}_{91}Pa + X \)
In the nuclear reaction above, X is

A\( ^0_1e \)

B\( ^0_{-1}e \)

C\( ^4_2He \)

D\( ^1_0n \)

E\( ^1_1p\)

View Explanation & Discuss

Question 997

neco 2008

When dust particles collide randomly in a beam of Sunlight, the phenomenon observed is known as

ABrownian movement.

BDialysis

CDiffusion

DOsmosis

ETyndall effect

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Question 998

neco 2008

The most efficient absorber of ultraviolet radiation in the atmosphere is

ACO₂

BH₂

CH₂O

D0₂

EO₃

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Question 999

neco 2008

Chlorine atom forms Cl- by

Adonating lone pair of electrons

Bgaining an electron

Closing an electron

Dsharing an electron

Esharing a lone pair of electrons.

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Question 1000

neco 2008

Which of the following laws is obeyed If at constant temperature, 200cm of hydrogen at 1.5 × 10m⁵Nm^-2pressure becomes 300cm³ at 1.0 × 10⁵Nm^-2 pressure?

AAvogadro’s

BBoyle’s

CCharles’

DFaraday’s

EGraham’s

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Question 1001

neco 2008

The type of reaction ethyne mainly undergoes is

Aaddition

Bcarboxylation.

Cesterification

Dsaponification

Esubstitution

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Question 1002

waec 2008

Which of the following alloys is mainly used in making statues?

ABrass

BBronze

CDuralumin

DSteel

View Explanation & Discuss

Question 1003

waec 2008

Aluminium is a good roofing material because it

Ais strong and does not conduct heat and electricity

Breadily absorbs light

Cforms an oxide film over its surface which prevents corrosion

Dis flexible and can conduct heat

View Explanation & Discuss

Question 1004

waec 2008

Chemicals that are produced in small quantities and with very high degree of purity are

Abulk chemicals

Bfine chemicals

Cheavy chemicals

Dlight chemicals

View Explanation & Discuss

Question 1005

waec 2008

Which of the following substances causes the depletion of the ozone layer in the atmosphere?

ACarbon (IV) oxide

BChlorofluorocarbon

CSulphur (IV) oxide

DHydrocarbons

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Question 1006

waec 2008

A solution of a salt was acidified with HCI when a few drops of BaCI₂ solution were added, a white precipitate was formed. Which of the following anions is present in the salt?

ACO^2- ₃

BNO^- ₃

CSO^2- ₄

DSO^2- ₃

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Question 1007

waec 2008

A hydrocarbon containing 88.9% carbon has the empirical formula [H = 1 C = 12]

ACH

BCH₂

CC₂H₃

DC₂H₅

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Question 1008

waec 2008

Arrange the following compounds in order of increasing boiling point
l.CH\(_3\)CH\(_2\)CH\(_2\)OH
II.CH\(_3\)CH\(_2\)OH
III.CH\(_3\)CH\(_2\)CH\(_2\)CH\(_2\)OH
IV.CH\(_3\)CH\(_2\)CH\(_2\)CH\(_2\)CH\(_3\)

AI < II < IV < III

BIV < III < II < I

CI < II < III < IV

DIV < II < I< III

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Question 1009

waec 2008

What is the main type of reaction alkenes undergo?

AAddition

BCondensation

CElimination

DSubstitutio

View Explanation & Discuss

Question 1010

waec 2008

The hydrolysis of groundnut oil by potassium hydroxide is known as

Ahydrogenation

Bsaponification

Cesteriffication

Dneutralization

View Explanation & Discuss

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