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Chemistry Past Questions

Study and practice Chemistry past questions with answers and detailed explanations. Then test your knowledge using our interactive CBT practice platform and prepare confidently for your upcoming examinations.

4,306 questions JAMB 2505 WAEC 1623 NECO 168 CUSTOM 10

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4,306 questions

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Question 981

neco 2008

The reaction of hydrochloric acid and calcium trioxocarbonate (IV) produces

Acalcium chloride, carbon (IV) oxide and water

Bcalcium chloride, and trioxocarbonate (IV) acid

Ccalcium hydroxide, carbon (IV) oxide and chlorine gas

Dcalcium hydroxide, carbon (IV) oxide and water

Ecalcium metal and water.

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Question 982

neco 2008

Brownian motion explains

ABoyle’s law

BCollision theory

CLaws of chemical combination

DMolecular motion in liquids and gases

EVibrational motion in liquids.

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Question 983

neco 2008

A chemical system is at equilibrium when

Aδ G is positive

Bδ G is zero

Cδ S is negative

Dδ S is positive

Eδ S is zero.

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Question 984

neco 2008

When sodium hydroxide solution is added to a solution of zinc salt, the white precipitate formed re-dissolve in excess sodium hydroxide because

Asodium hydroxide is a strong alkali

Bsodium is more reactive than zinc

Czinc is more reactive than sodium

Dzinc hydroxide is amphoteric

Ezinc hydroxide is unstable

View Explanation & Discuss

Question 985

neco 2008

The gas in air used by plants for photosynthesis is

AArgon

BCarbon (IV) oxide

CNitrogen

DOxygen

EWater vapour.

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Question 986

neco 2008

Which of these arrangement of elements is in order of increasing ionization energy?

ABoron, Carbon, Flourine, Nitrogen

BBoron, Carbon, Nitrogen, Flourine

CCarbon, Boron, Nitrogen, Flourine

DFlourine, Nitro9en, Carbon, Boron

ENitrogen, Flourine, Carbon, Boron

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Question 987

neco 2008

The following acids are monobasic EXCEPT

Adioxonitrate (Ill) acid

Bethanedioic acid

Chydrobromic acid

Dmethanoic acid

Eoxochlorate (I) acid

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Question 988

neco 2008

An element Z has a combining power of 3. Which of the following formulae is correct of its compound?

AZS₃

BZSO₃

CZS0₄

DZ₂0₃

EZ₃Cl₂

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Question 989

neco 2008

Bauxite is the ore of

Aaluminium

Bcalcium

CIron

Dsodium

Emagnesium

View Explanation & Discuss

Question 990

neco 2008

Matter is neither created nor destroyed in the course of any chemical reactions is a statement of the law of

Acombining volumes

Bconservation of mass

Cdefinite proportion

Dmultiple proportion

Ereciprocal proportion.

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Question 991

neco 2008

pH is define as

A[H+]

B–log [H]

C–log [H+]

Dlog [H]

Elog [H+]

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Question 992

neco 2008

Which of the following compounds is unsaturated?

ACyclohexane

BMethoxyethane

C1 ,2-dibromoethane

D2,2,3-trimethylpentane

E3-methylbut-l-ene

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Question 993

neco 2008

A solution is prepared by dissolving I .96g of H₂SO₄ in 250 cm³ of its solution. What is the concentration in moles per dm³?

A0.008

B0.08

C0.1

D0.8

E8.02

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Question 994

neco 2008

The action of zinc on an acid produces

Achlorine

Bhydrogen

Cnitrogen

Dsulphur

Ewater vapour.

View Explanation & Discuss

Question 995

neco 2008

The high boiling point of hydrogen fluoride can be explained in terms of?

Acovalent bonds.

Bdative bonds.

Cdipole-dipole bonds

Delectrovalent (ionic) bonds.

Ehydrogen bonds.

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Question 996

neco 2008

What type of bond holds hydrogen fluoride molecules together when forming larger aggregate?

ACovalent

BDative

CHydrogen

DIonic

EMetallic

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Question 997

neco 2008

A device used in the laboratory for intermittent production of gases without heating is

Aaspirator

Bdelivery tube

Cfume cupboard

Dkipp’s apparatus

Emuller counter

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Question 998

neco 2008

If two metallic ions of the same concentration migrate to a graphite cathode, the one that would be preferentially discharged is that with the

Agreater stability in solution

Blower electrical charge

Csmaller mass

Dstronger tendency to accept electrons

Estronger tendency to lose electrons.

View Explanation & Discuss

Question 999

neco 2008

The planet with the highest number of moon is

AEarth

BJupiter

CUranus

DPluto

EVenus.

View Explanation & Discuss

Question 1000

neco 2008

Pipe-borne water is usually chlorinated in order to

Acoagulate sediments in the water

Bimprove taste of the water

Ckill harmful bacteria in the water

Dmake it pure

Eremove the hardness in the water

View Explanation & Discuss

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