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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.

1,623 questions JAMB 2505 WAEC 1623 NECO 168 CUSTOM 10

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1,623 questions

Question 1 of 20 1,623 total questions

Question 241

waec 2016

Which of the following apparatus can be used to measure a specific volume of a liquid accurately?

ABeaker

BConical flask

CMeasuring cyclinder

DPipette

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Question 242

waec 2016

Which of the following statements about solids is correct?

ASolid particles are less orderly than those of a liquid

BSolid have lower densities than liquids

CSolid particles have greater kinetic energies than those of liquids

DSolid particles cannot be easily compressed

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Question 243

waec 2016

How many moles of oxygen would contain 1.204 x 10²⁴ molecules?
[Avogadro's constant (NA) = 6.02 x 10²³]

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Question 244

waec 2016

An element X froms the following oxides X₂O, XO and XO₂. This phenomenon illustrates the law of________?

AConservation of mass

BDefinite proportion

CMass action

DMultiple proportion

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Question 245

waec 2016

The bond formed between H₂O and H₊ to form the hydroxonium H₃O₊ is

ADative

BCovalent

CElectrovalent

DIonic

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Question 246

waec 2016

The minimum amount of energy required for effective collisions between reacting particles is known as

AActivation energy

BBond energy

CKinetic energy

DPotential energy

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Question 247

waec 2016

Which of the following elements would produce coloured ion in agueous solution?

ACalcuim

BCopper

CMagnesuim

DSodium

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Question 248

waec 2016

The shape of the water molecule is_______?

ALinear

BPyramidal

CTetrahedral

DV-shaped

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Question 249

waec 2016

Which of the following arrangements shows increasing order of reactivity of the halogens?

AF₂ > Cl₂ > Br₂ >I₂

BI₂ < Br₂ < Cl₂< F₂

CF₂ < Cl₂ < Br₂< I₂

DI₂ > Br₂ > Cl₂ > F₂

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Question 250

waec 2016

An unsaturated solution differs from a saturated solution at a given temperature because it

ACannot dissolve more solute

BCan hold more solute than it can actually dissolve

CCan still dissolve more solute at given temperature

DForm crystal more easily on cooling

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Question 251

waec 2016

Aluminium is used in the manufacture or aircraft because it

AIs hard and brittle

BIs light and resists corrosion

CHas high density and conducts electricity

DIs malleable and ductile

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Question 252

waec 2016

Metals can be stretched into wires because they are

ADuctile

BGood conductors

CLustrous

DMalleable

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Question 253

waec 2016

The mass of potassium hydroxide required to make 300.ocm³ of 0.4 moldm^-3 solution is {KOH = 56.0}

A26.88g

B13.44g

C6.72g

D3.36g

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Question 254

waec 2016

Chemicals that are produced in small quantities and with very degree of purity are

ABulk chemicals

BFine chemicals

CHeavy chemicals

DLight chemicals

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Question 255

waec 2016

The boiling points of HF, H2O and NH3 increase in the order of

ANH₃

BH₂O < HF

CHF < NH₃ < H₂O

DNH₃ < HF < H₂O

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Question 256

waec 2016

When element \(_{20}\)Y combines with element \(_8\)Z, it forms

AA covalent compound , YZ is formed

BA covalent compound, ZY is formed

CAn ionic compound, YZ is formed

DAn ionic compound, ZY is formed

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Question 257

waec 2016

How many electrons are present in \(^9_4Be^{2+}\)?

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Question 258

waec 2016

An atom X consist of 6 protons, 6 electrons and 7 neutrons. Which of the following representations of the atom is correct?

A¹³₆X

B¹³₇X

C¹⁹₆X

D¹⁹₇X

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Question 259

waec 2016

The following atoms of carbon ¹²₆C, ¹³₆C and ¹⁴₆C can be described as?

AAllotropes

BIsomers

CIsotopes

DIsotones

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Question 260

waec 2015

Consider the following equilibrium system:
2SO_2(g) + O_2(g) \(\rightleftharpoons\) 2SO_3(g)

The addition of more O_2(g) to the system will shift the equilibrium position to the

ARight leading to the production of more SO_3(g)

BRight leading to the production of more SO_2(g)

CLeft leading to the production of more SO_2(g)

DLeft leading to the production of more SO_3(g)

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