Chemistry Past Questions

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2,505 questions JAMB 2505 WAEC 1623 NECO 168 CUSTOM 10
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Past Questions

2,505 questions
Question 1 of 20 2,505 total questions
Question 541
jamb 2008

The IUPAC nomenclature for the structure above is

A2, 3 - dichloro - 4, 4, 5 - trimethyl pent - 2 - ene
B4, 5 - dichloro - 2, 3 - dimethyl hex - 2 - ene
C2, 3 - dichloro - 4, 4 - dimethyl hex - 2- ene
D2, 3 dichloro - 2, 2 - dimethyl hex - 2 - ene
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Question 542
jamb 2008

If glucose is heated with concentration tetraoxosulphate (VI) acid, it will be dehydrated to

Acarbon
Bcarbon (IV) oxide
Cethene
Dethanol
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Question 543
jamb 2008

If the silver mirror test is positive, it indicates the presence of an

Aalkyne
Balkanol
Calkanone
Dalkanal
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Question 544
jamb 2008

The type of isomerism shown by cis- and trans- isomers is

Aoptical isomerism
Bpositional isomerism
Cfunctional isomerism
Dgeometrical isomerism
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Question 545
jamb 2008

The most common ores of iron include

Ahaematite, malachite and limonite
Bchalcocite, calamine and bornite
Cmagnetite, haematite and limonite
Dmagnetite, chalcocite and bornite
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Question 546
jamb 2008

which of the following gives a precipitate when treated with NaOH solution?

AAlCl3
BNH4Cl
CNa2CO3
DCH3COONa
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Question 547
jamb 2008

Leads is used for making bullets and lead shots because of its

Aresistance to corrosion
Blow melting point
Chigh density
Dflexibility
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Question 548
jamb 2008

When a solution of ammonium trioxocarbonate (IV) is added to a solution of an unknown salt, a white precipitate which is soluble in dilute hydrochloric acid but insoluble in ethanoic acid is formed. This indicates the presence of

ACa2+
BNa+
CZn2+
DK+
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Question 549
jamb 2008

Which of the following compounds of trioxonitrate (V) will decompose to give dinitrogen (i) oxide and water when heated?

ANaNO3
BZn(NO3)2
CCu(NO3)2
DNH4NO3
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Question 550
jamb 2008

The substance that is used in the steel industry for the removal of carbon, sulphur and phosphorus impurities from pig iron is

Aoxygen
Bchlorine
Cnitrogen
Dhydrogen
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Question 551
jamb 2008

The rate of a reaction usually decreases with a decrease in the concentration of reactants because

Akinetic energy decrease
Btemperature increase
Cspeed increases
Dreactants collision decrease
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Question 552
jamb 2008

A catalyst speeds up the rate of chemical reaction by

Ataking part in the reaction
Bincreasing the activation energy of the reaction
Clowering the activation energy of the reaction
Dincreasing the heat content
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Question 553
jamb 2008

Which of the following reaction is endothermic?

AC(s) + O2(g) → CO2(g)
BCaO(s) + H2O(l) → Ca(OH)2(s)
CC(s) + H2O(g) → CO(g) + H2(g)
DHCl(aq) + NaOH(aq) → NaCl(aq) + H2O(l)
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Question 554
jamb 2008

\(NH_{3(g)} + HCl_{(g)} → NH_4Cl_{(s)}\)
The entropy change in the system above is

Apositive
Bzero
Cnegative
Dindeterminate
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Question 555
jamb 2008

If a given quantity of electricity liberates 0.65g of Zn2+, what amount of Hg2+ would be liberated by the same quantity of current?
[Zn = 65, Hg = 201]

A1.00g
B2.01g
C4.02g
D8.04g
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Question 556
jamb 2008

In recharging a lead-acid accumulator, the reaction at the cathode can be represented as

APb2+(aq) + SO2-4(aq) →PbSO4(s)
BPb2+(aq) + 2e- →Pb(s)
CPb2+(aq) + 2H2O(l) → PbO2(s) + 4H+(aq) + 4e-
DPb(s) → Pb2+(aq) + 2e-
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Question 557
jamb 2008

What is the IUPAC nomenclature of the compound NaCIO?

Asodium oxochlorate (I)
Bsodium chloro (I) oxide
Csodium monooxochlorate (II)
Dsodium chloro (I) monoxide
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Question 558
jamb 2008

The oxidation state of carbon in HCOOH is

A-1
B+2
C+3
Dzero
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Question 559
jamb 2008

Insoluble salts can be prepared by?

Atitrating an alkali against an appropriate acid
Breacting an acid with trioxocarbonate (IV) salt
Cdirecting combination of the elements which make up the salt
Dmixing two soluble compounds containing the metallic radical and the acidic radical
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Question 560
jamb 2008

0.05 mol dm-3 HCl is neutralized by 25 cm3 NaOH. If the volume of acid used is 32.00cm3, what is the concentration of the base

A0.016 mol dm-3
B0.032 mol dm-3
C0.039 mol dm-3
D0.064 mol dm-3
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