Chemistry Past Questions

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4,306 questions JAMB 2505 WAEC 1623 NECO 168 CUSTOM 10
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Past Questions

4,306 questions
Question 1 of 20 4,306 total questions
Question 161
jamb 2024

How many moles of CO\(_2\) are produced when ethanol is burnt with 6g of oxygen

A0.125
B0.250
C0.375
D0.750
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Question 162
jamb 2024

For chemical reaction to be spontaneous, ∆G must be

Apositive
Bnegative
Czero
Dequal to the enthalpy change
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Question 163
jamb 2024

The chemical formula for potassiumhexacyanoferrate(II) is

A[Fe(CN)\(_6\)]\(^{4-}\)
BK\(_3\)Fe(CN)\(_6\)
CFe(CN)\(_6\)
DK\(_4\)Fe(CN)\(_6\)
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Question 164
jamb 2024

Strong acids can be distinguished from weak acids by any of the following methods, EXCEPT

AConductivity measurement
BThe use of litmus paper
CMeasurement of pH
DMeasurement of heat of reaction
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Question 165
jamb 2024

The pH of a 0.001 mol dm\(^{-3}\) of  H\(_2\)SO\(_4\) is 

[Log\(_{10}\)2 = 0.3]

A2.7
B3.0
C3.3
D2.0
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Question 166
jamb 2024

The table above shows the formulae of some ions. In which of these compounds is the formula not correct?

AAluminiumtetraoxosulphate(VI), Al\(_2\)(SO\(_4\))\(_3\)
BCalciumtrioxonitrate(V), Ca(NO\(_3\))\(_2\)
CIron(III)bromide, Fe\(_3\)Br
DPotassiumsulphide, K\(_2\)S
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Question 167
jamb 2024

What would be the order of the electrolytic cell in an industry intending the production of silver plated spoons?

ACathode is the spoon; anode is a silver rod; electrolyte is a soluble silver salt
BCathode is a silver rod; anode is the spoon; electrolyte is a soluble silver salt
CCathode is the spoon; anode is any rod; electrolyte is a soluble silver salt
DCathode is any rod; anode is the spoon; electrolyte is a soluble salt
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Question 168
jamb 2024

The quantity of electricity required to deposit 180g of Ag from a molten silver trioxonitrate(V) is

[Ag = 108]

A1.08F
B3.30F
C1.67F
D1.80F
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Question 169
jamb 2024

127g of sodium chloride was dissolved in 1.0dm\(^3\) of distilled water at 25\(^0\)C . Determine the solubility in moldm\(^{-3}\) of sodium chloride at that temperature. [Na = 23, Cl = 35.5] 

A1.0
B2.0
C2.2
D4.1
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Question 170
jamb 2024

If the solubility of KNO\(_3\) at 30\(^0\)C is 3.10 mol/dm\(^3\) a solution containing 303g/dm\(^3\) KNO\(_3\) is likely to be

Asaturated
Bunsaturated
Csupersaturated
Dat saturation point
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Question 171
jamb 2024

When a few drops of Millon reagents is added to egg-white solution in a test tube, the white precipitate changes to

Aorange
Bbrick red
Creddish brown
Dblue
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Question 172
jamb 2024

How many isomers has the organic compound represented by the formula C\(_3\)H\(_8\)O ?

A2
B3
C4
D5
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Question 173
jamb 2024

The number of geometrical isomers of butene are 

A2
B3
C5
D4
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Question 174
jamb 2024

A gas when mixed with oxygen, it produces a very hot and early controllable flame. What is the name of the flame and where is it used?

AAcetylene flame; miners' lamb
BOxy-ethylene ; hunters' torch
COxy-ethylene flame; miners' lamb
DOxy-ethylene flame ; cutting and welding metals
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Question 175
jamb 2024

Biuret test is a chemical test used for detecting the presence of 

Acarbohydrates
Bproteins
Camines
Dalkanoates
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Question 176
jamb 2024

The empirical formula of an organic liquid hydrocarbon is XY. If the relative molar masses of X and Y are 72 and 6 respectively, it's vapour density is likely to be

A33
B66
C39
D78
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Question 177
jamb 2024

An organic compound contains 53.1% Carbon, 6.2% Hydrogen, 12.4% Nitrogen, and 28.3% Oxygen by mass. What is the molecular formula of the compound if its vapour density is 56.5?   [ C =12, H = 1, N = 14, O = 16]. 

AC\(_5\)H\(_7\)NO\(_2\)
BC\(_5\)H\(_6\)NO\(_2\)
CC\(_3\)H\(_6\)NO\(_2\)
DC\(_3\)H\(_7\)NO\(_2\)
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Question 178
jamb 2024

A liquid hydrocarbon obtained from fractional distillation of coal tar that is used in the pharmaceutical industry is

Axylene
Bbenzene
Chexane
DToluene
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Question 179
jamb 2024

During the fractional distillation of crude oil, the fraction that distills at 200 - 250\(^0\) C is

Abitumen
Bdiesel
Ckerosene
Dpetrol
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Question 180
jamb 2024

The constituent of petroleum fraction used in surfacing road is

Apetrol
Bdiesel
Clubricating oil
Dbitumen
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