Chemistry Past Questions

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50 questions JAMB 2505 WAEC 1623 NECO 168 CUSTOM 10
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Past Questions

50 questions
Question 1 of 20 50 total questions
Question 11
waec 2019

Which of the following reagents could be used to distinguish between propan-1-ol and propan-2-ol ?

AH+ / K2Cr2O7
BI\(_2\) / OH\(^-\)
CCH\(_3\)COOH
DNaCl
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Question 12
waec 2019

When excess chlorine is mixed with ethane at room temperature, the product formed is?

A1,2-dichloroethane
B1,2-dichloroethene
C1,1-dichloroethane
D1,1-dichloroethene
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Question 13
waec 2019

An organic compound contains 72% carbon, 12% hydrogen and 16% oxygen by mass. What is the empirical formula of the compound?

[ H = 1.0. C = 12.0, O = 16.0 ]

AC\(_3\)H\(_8\)O
BC\(_6\)H\(_{12}\)O
CC\(_6\)H\(_{12}\)O\(_2\)
DC\(_{12}\)H\(_{12}\)O\(_{11}\)
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Question 14
waec 2019

What is the characteristic of the gas liberated when dilute hydrochloric acid is added to Iron(ii)sulphide?

Aturns lime water milky
Bdecolorizes bromine water
Cgives a pop sound
Dturns lead(ii)ethanoate paper black
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Question 15
waec 2019

Which of the following compounds is formed by the oxidation of ethanol?

AC\(_2\)H\(_4\)CO\(_2\)H
BC\(_2\)H\(_5\)CO\(_2\)H
CCH\(_3\)OH
DCH\(_3\)CO\(_2\)H
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Question 16
waec 2019

If the value of ΔH is positive for a reaction, it means that the reaction is?

Aexothermic
Bendothermic
Cspontaneous
Dslow
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Question 17
waec 2019

When quicklime dissolves in water?

Aheat is absorbed
Bheat is evolved
Coxygen is liberated
Dhydrogen is given off
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Question 18
waec 2019

which of the following pairs of substances has the highest heat of neutralization?

Astrong acid and strong base
Bweak acid and weak base
Cstrong acid and weak base
Dweak acid and strong base
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Question 19
waec 2019

consider the following reaction equation: 2Al(OH)\(_3\) + 3H\(_2\)SO\(_4\) →Al\(_2\)(SO4)\(_3\)(aq)+6H\(_2\)O. How many moles of tetraoxosulphate(vi)acid is needed to produce 0.5mol of aluminium tetraoxosulphate(vi)?

A0.5
B1.0
C1.5
D3.0
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Question 20
waec 2019

The most suitable indicator for the reaction between NaOH and HCOOH is?

Abromocresol
Bmethyl orange
Cmethyl red
Dphenolphthalein
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Question 21
waec 2019

A sample of air was bubbled into water. The PH of the water slowly changed from 7 to 6. Which of the following gases in the samples caused the change?

Acarbon(iv)oxide
Bcarbon(ii)oxide
Cnitrogen
Doxygen
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Question 22
waec 2019

which of the following solutions containing one mole per dm\(^3\) of the compound would have the lowest PH?

Aethanoic acid
Bhydrochloric acid
Csodium chloride
Dsodium hydrogentrioxocarbonate(iv)
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Question 23
waec 2019

Vinegar is an aqueous solution of?

AHydrochloric acid
Bethanedioc acid
Cethanoic acid
Dhydrofluoric acid
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Question 24
waec 2019

What is the solubility of a salt X at 25ºC if the saturated solution of the salt contains 0.28g in 100cm\(^3\) of the solution in mol\dm\(^3\)? 

[ X = 56.0g ]

A0.05
B0.10
C2.60
D2.80
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Question 25
waec 2019

The properties of a good primary standard solution include the following except?

AHigh molecular mass
Blow molecular mass
Chigh degree of purity
Dreadily available
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Question 26
waec 2019

The name of the compound CH\(_3\)C(CH\(_3\))\(_2\)CH\(_2\)CH\(_2\)CH\(_3\)

A2 - methyl butane
B2,2 - dimethyl butane
C2 - methyl pentane
D2,2 - dimethyl pentane
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Question 27
waec 2019

Which of the following compounds has coordinate bonds in its structure?

AAl\(_2\)Cl\(_6\)
BMgCl\(_2\)
CAgCl
DNaCl
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Question 28
waec 2019

What is the percentage by mass of H in  CH\(_3\)COOH ?

A1.7%
B5.0%
C6.7%
D7.1%
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Question 29
waec 2019

Stoichiometry is based on the law?

Amultiple proportion
Bconstant composition
Cconservation of energy
Dconservation of mass
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Question 30
waec 2019

How many moles of carbon(iv)oxide contains 16.0g of oxygen?

[ C = 12.0, O = 16.0 ]

A0.20 mol
B0.25 mol
C0.40 mol
D0.50 mol
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