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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

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Question 641

waec 2015

The shape of a molecule of water is _______?

ANon-linear

BOctahedral

CPyramidal

DTetrahedral

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Question 642

waec 2015

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

AXY

BXY₂

CX₂Y

DX₄Y₆

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Question 643

waec 2015

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

AAmmonium chloride

BChlorine

CSodium chloride

DWater

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Question 644

waec 2015

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

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Question 645

waec 2015

The negatively charged particle in an atom is the

AElectron

BNeutron

CPositron

DProton

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Question 646

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 647

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 648

jamb 2015

In the electrolysis of brine the anode is

Aplatinum

Bcopper

Czinc

Dcarbon

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Question 649

jamb 2015

The oxidation state of sulphur on H2SO4 acid is

A-4

B+6

D-8

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Question 650

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 651

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 652

jamb 2015

The principal constituent of natural gas is

Amethane

Bethane

Cpropane

DButane

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Question 653

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 654

jamb 2015

Chlorine gas turns damp starch-iodide paper

Apink

Bcolourless

Cred

Ddark blue

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Question 655

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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Question 656

jamb 2015

what is the pH of 0.00lmoldm³ solution of sodium hydroxide

A14

B13

C12

D11

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Question 657

jamb 2015

Which of the following compounds can be represented by the molecular formula C2 H6O?

Apropanal

Bethanol

Cmethanoic acid

Dglucose

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Question 658

jamb 2015

If glucose is heated with concentrated tetraoxosulphate(vi)acid, it will be dehydrated to?

Acarbon

Bcarbon(iv)oxide

Cethane

Dethanol

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Question 659

jamb 2015

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 660

jamb 2015

In countries where the temperature fall below 273k, salt always spilled on the road in order to

Aincrease the boiling point

Bincrease the density of the ice

Cmake the ice impure

Dreduce the freezing point of ice

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