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Chemistry Past Questions

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114 questions JAMB 2505 WAEC 1623 NECO 168 CUSTOM 10

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114 questions

Question 1 of 20 114 total questions

Question 21

waec 2015

The gas given off when ethanol reacts with sodium is

ACarbon(IV)oxide

BHydrogen

CMethane

DOxygen

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Question 22

waec 2015

The following transition metal ions would be coloured in aqueous solution except________?

ACr³⁺

BFe³⁺

CMn³⁺

DSc³⁺

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Question 23

waec 2015

Which of the following pairs of compounds belongs to the same homologous series?

AC₃H₈ and C₃H₆

BC₄H₁₀ and C₅H₁₀

CC₂H₄ and C₄H₁₀

DC₂H₆ and C₄H₁₀

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Question 24

waec 2015

Which of the following pairs of elements forms amphoteric oxides?

ABe and Mg

BNa and K

CB and Al

DSi and Pb

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Question 25

waec 2015

A metallic ion Z\(^{2+}\) with an inert gas structure contains 18 electrons. How many protons are contained in this ion?

A20

B18

C16

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Question 26

waec 2015

The shape of a molecule of water is _______?

ANon-linear

BOctahedral

CPyramidal

DTetrahedral

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Question 27

waec 2015

The compound formed between ₁₄X and ₁₆Y is _______?

AXY

BXY₂

CX₂Y

DX₄Y₆

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Question 28

waec 2015

The Van der waals' forces are dominant intermolecular forces in_______?

AAmmonium chloride

BChlorine

CSodium chloride

DWater

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Question 29

waec 2015

How many orbits are contained in an atom with atomic number 13?

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Question 30

waec 2015

The negatively charged particle in an atom is the

AElectron

BNeutron

CPositron

DProton

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Question 31

jamb 2015

When steam is passed over red hot carbon the substances produced are

Ahydrogen and trioxocarbonate (IV) acid

Bhydrogen, oxygen and carbon (IV) oxide

Chydrogen and carbon (ii) oxide

Dhydrogen and carbon (IV) oxide

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Question 32

jamb 2015

Calculate the relative molecular mass of Limestone CaCO3, (Ca = 40, C =12, O = 16)

A56

B100

C76

D90

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Question 33

jamb 2015

In the electrolysis of brine the anode is

Aplatinum

Bcopper

Czinc

Dcarbon

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Question 34

jamb 2015

The oxidation state of sulphur on H2SO4 acid is

A-4

B+6

D-8

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Question 35

jamb 2015

S block elements of the periodic table one made up of

Agroups 1, 2, 3

Bgroups 1, and 2

Cgroup 3

Dgroup 3 to 7

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Question 36

jamb 2015

In the electrolysis of CuSo4(g) using platinum electrode the reaction at the anode is

A4H+ 4e - 2H₂

B4OH⁼ 4e- + 2H₂O + O₂

C2OH - 2e_- = 2OH

D2OH^- + 2OH = 2H₂O + O₂

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Question 37

jamb 2015

The principal constituent of natural gas is

Amethane

Bethane

Cpropane

DButane

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Question 38

jamb 2015

Chlorine consisting of two isotope of mass number 35 and 37 in the ratio 3:1 has an atomic mass of 35.5. Calculate the relative abundance of the isotope of mass number 37

A20

B25

C60

D75

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Question 39

jamb 2015

Chlorine gas turns damp starch-iodide paper

Apink

Bcolourless

Cred

Ddark blue

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Question 40

jamb 2015

N₂O_4(g)→ 2NO_2(g)

In the endothermic reaction above, more products formed will be favored by

AA constant values

Ban increase in pressure

Ca decrease pressure

Da decrease volume

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