Chemistry Past Questions

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

1,623 questions
Question 1 of 20 1,623 total questions
Question 81
waec 2022

Which of the following statements about atoms of a metal is correct? They

Areadily accept electrons
Bare soft
Care held together by covalent bond
Dare held together by a sea of electron cloud
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Question 82
waec 2022

An oxide has the following properties. It


I. is a white powder
II. reacts with HCI.
III. reacts with NaOH
IV. is insoluble in water
The oxide is

Aalkaline
Bamphoteric
Cacidic
Dneutral
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Question 83
waec 2022

The electron configuration of carbon atom in its excited state is

A1s\(^{2}\)2s\(^{2}\)2px\(^{1}\)2py\(^{1}\)
B
C1s\(^{2}\)2s\(^{1}\)2px\(^{1}\)2py\(^{1}\)2pz\(^{1}\)
D1s\(^{1}\)2s\(^{2}\)2px\(^{1}\)2py\(^{1}\)
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Question 84
waec 2022

Which of the following properties indicate that an element is a metal. It


I. reacts with oxygen to form an acidic oxide
II. forms ionic chlorides
III. has variable oxidation states
IV. displaces hydrogen from dilute HCl

AI and III only
BI and II only
CII and IV only
DI, II, III and IV
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Question 85
waec 2022

Ionization energy increases across the period in the periodic table because

Aatomic number increases
Beffective nuclear charge increases
Cmass number decreases
Dscreening effect decreases
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Question 86
waec 2022

The IUPAC name of the compound CH3CH(CH3)CHCH2 is

A2 - methyl but - 1 - ene
B2 - methyl but - 2 - ene
C3 - methyl but - 1 - ene
D3 - methyl but - 2 - ene
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Question 87
waec 2022

The maximum number of covalent bonds formed by nitrogen is

A1
B2
C3
D4
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Question 88
waec 2022

Which of the following bond types is intermolecular?

ACovalent bond
BHydrogen bond
CIonic bond
DMetallic bond
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Question 89
waec 2022

What is the percentage composition of carbon
in Ca(HCO3)\(_{2}\) ?
[ Ca = 40.0, 0= 16.0, C = 12.0, H= 1.0]

A22.2%
B14.8%
C7.4%
D3.7%
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Question 90
waec 2022

Which of the following elements would displace copper from a solution of copper ions?

Asilver
Bgold
Clead
Dmercury
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Question 91
waec 2022

If 50 cm\(^{3}\) of a saturated solution of KNO\(_{3}\) at 40 °C contained 5.05 g of the salt, its solubility at the same temperature would be
[KNO\(_{3}\) = 101]

A1.0 mol dm\(^{-3}\)
B1.5 mol dm\(^{-3}\)
C2.0 mol dm\(^{-3}\)
D5.0 mol dm\(^{-3}\)
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Question 92
waec 2022

What number of moles of oxygen would exert a pressure of 10 atm at 320 K in an 8.2 dm\(^{3}\) cylinder?
[R=0.082 atm dm\(^{-3}\) mol\(^{-1}\) K\(^{-1}\)]

A0.32
B1.52
C3.13
D31.25
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Question 93
waec 2022

A hydrogen chloride gas reacted with oxygen gas to yield water and chlorine gas. The mole ratio of the hydrogen chloride gas to water is

A1:3
B2:1
C3:1
D4:1
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Question 94
waec 2022

Which of the following statements about liquids is/are true?


I. Liquids maintain their volume at constant temperature.
II. Liquids have fixed shape
III. Liquids do not diffuse
IV. Change in pressure affects volume of liquids

AI only
BIV only
CI and IV only
DII and III only
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Question 95
waec 2022

When air in a syringe is compressed such that there is no change in temperature, the

Aair liquefies
Bpressure increases
Cintermolecular space increases
Ddensity decreases
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Question 96
waec 2022

Consider the following reaction equation
N\(_{2}\)(g) + 3H\(_{2(g)}\)  ⇌ 2NH3(g) ∆H = -92kJ

Increasing the temperature of the reaction would

Ashift the equilibrium to the right
Bincrease the yield of ammonia
Cdecrease the amount of hydrogen
Ddecrease the yield of ammonia
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Question 97
waec 2022

Which of the following statements about an equilibrium system is correct?

AForward and backward reactions occur
at the same rate
BThe concentrations of reactants must
equal that of the products
CThe concentrations of, reactants and products can be changed by adding a catalyst,
DThe concentrations of reactants and
products are not affected by a change in temperature
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Question 98
waec 2022

Which of the following gases is alkaline?

ANO\(_{2}\)
BCO\(_{2}\)
CNH\(_{3}\)
DN\(_{2}\)O
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Question 99
waec 2022

Graphite is used as a dry lubricant due to the presence of

Amobile electrons
Bfree electrons
Coctahedral structures
Dlayered structures
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Question 100
waec 2022

What is the partial pressure of oxygen at s.t.p. in a gaseous mixture containing 100 cm3 of oxygen and 900 cm3 of nitrogen gas?

A1.0 atm
B0.1 atm
C9.0 atm
D0.9 atm
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