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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 1301

waec 2002

Which of the following ions require the largest quantity of electricity for discharge at an electrode?

A2.0 mole of Q ³⁺

B2.5 mole of R²⁺

C4.0 mole of Y^-

D3.0 mole of T^-

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Question 1302

waec 2002

Consider the following equation; Cr₂O_7(aq)^2- + 14H⁺_(aq) + 6e^- → 2Cr³⁺_(aq) + 7H₂O_(I). The oxidation number of chromium changes from

A-2 to + 3

B- 2 to + 6

C+ 6 to + 3

D+ 7 to + 6

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Question 1303

waec 2002

The atomic number of chlorine is 17. What is the number of electrons in a chloride ion?

A16

B17

C18

D19

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Question 1304

waec 2002

If the relative molecular mass of an element is not a whole number, it can be deduced that the element is

Anaturally radioactive

Babundant in nature

Ca transition metal

Dan isotopic mixture

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Question 1305

jamb 2002

The compound above is

Aglycol

Bprimary alkanol

Csecondary alkanol

Dtertiary alkanol

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Question 1306

jamb 2002

The major product of the dehydration of the compound above is?

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Question 1307

jamb 2002

In the diagram above, the curve that represents the production of oxgyen gas from the decomposition of KCIO3 in the presence of MnO2 catalyst is

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Question 1308

jamb 2002

If 0.75 mole of cyclopropane and 0.66 mole of oxygen are mixed in vessel with a total pressure of 0.7 atmosphere, what is the partial pressure of oxygen in the mixture

A0.44 atmosphere

B0.22 atmosphere

C0.55 atmosphere

D0.33 atmosphere

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Question 1309

jamb 2002

\(^{14}\) \(_6\)C → X + β
X in the equation above represents

A¹²₆C

B¹²₅B

C¹⁴₇N

D¹³₆C

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Question 1310

jamb 2002

The postulate of Dalton's atomic theory which still holds is that

Aatoms can neither be created nor destroyed

Bthe particles of the same element are exactly alike

Cparticles of different elements combine in simple whole number ratio

Dall elemets are made of small indivisible particles

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Question 1311

jamb 2002

The processes which return carbon (IV) oxide to the atmosphere include

Arespiration, decay and combustion

Bphotosynthesis, respiration and transpiration

Cozone depletion, combustion and decay

Dphotosynthesis, decay and respiration

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Question 1312

jamb 2002

A fixed mass of gas has a volume of 92\(cm^3\) at 3ºC. What will be its volume at 18ºC if the pressure remains constant?

A15.3cm³

B87.3cm³

C552.0cm³

D97.0cm³

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Question 1313

jamb 2002

Which of the following chloride would exhibit the least ionic character?

AMgCl₂

BCaCl₂

CLiCl

DAlCl₃

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Question 1314

jamb 2002

Which of the following statement is true of a proton?

AThe mass of a proton is 1840 times the mass of electron

Bthe total mass of the protons in a particular nucleus is always half the nuclear size

CThe mass of a proton is one - twelfth the molar mass of carbon

DThe mass of a proton is 1.0008g

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Question 1315

jamb 2002

A rock sample was added to cold dilute HNO3. The gas evolved was passed into a solution of acidified K2Cr2O7 and the solution turned green. The sample contains

ACl^-

BNO₃^-

CSO₃^2-

DSO₄^2-

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Question 1316

jamb 2002

The intermediate product formed when ethanol is progressively oxidized to ethanoic acid with potassium heptaoxodichromate (IV) is

Abutanal

Bethanal

Cmethanal

Dpropanal

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Question 1317

jamb 2002

Hydrogen is readily released when dilute hydrochloric acid reacts with

ACu

BNa

CAu

DAg

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Question 1318

jamb 2002

which of the following polymers is suitable for packaging and electrical insulation?

Apolyamide

Bpolyethene

Cpolycarbonate

Dpolystyrene

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Question 1319

jamb 2002

The most important use of hydrogen is in the

Amanufacture of ammonia

Bmanufacture of methyl alcohol

Cmanufacture of ethyl alcohol

Dhydrogenation of oils

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Question 1320

jamb 2002

The boiling of fat and aqueous caustic soda is referred to as

Ahydrolysis

Besterification

Cacidification

Dsaponification

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