Chemistry Past Questions

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Past Questions

4,306 questions
Question 1 of 20 4,306 total questions
Question 281
jamb 2022

In which of the following will hydrogen form ionic compound? 

AHCL
BNaH
CNH\(_3\)
DCH\(_4\)
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Question 282
jamb 2022

2H\(_2\) + O\(_2\) → 2H\(_2\)O

From the equation above, calculate the volume of unreacted oxygen gas if a mixture of 50cm\(^3\) of hydroden and 75cm\(^3\) of oxygen are involved

A85cm\(^3\)
B50cm\(^3\)
C125cm\(^3\)
D55cm\(^3\)
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Question 283
jamb 2022

An organic compound contains 69% carbon, 15.3% hydrogen and 30.7% oxygen. Calculate the the empirical formula [C=12, H = 1, O = 16]

AC\(_4\)H\(_12\)O
BC\(_3\)H\(_9\)O
CC\(_4\)H\(_9\)O
DC\(_3\)H\(_8\)O
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Question 284
jamb 2022

Crude petroleum is converted to useful products by the process of?

Afractional crystallization
Bfractional distillation
Cfiltration
Dchromatography
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Question 285
jamb 2022

An organic compound which decolorizes bromine water is likely to be?

AC\(_3\)H\(_8\)
BC\(_2\)H\(_6\)
CC\(_4\)H\(_10\)
DC\(_2\)H\(_4\)
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Question 286
jamb 2022

In order to electroplate spoon with silver, the arrangement of the electrolytic cell is?

Athe anode is a silver rod and the cathode is the spoon
Bthe anode is the spoon and the cathode is a silver rod
Cthe electrolyte is silver trioxonitrate(v)( solution and the cathode is a silver rod.
Dthe electrolyte is silver trioxonitrate(v) solution and the anode is the spoon
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Question 287
jamb 2022

A colored gas that is known to be poisonous and can readily damage the mucous lining of the lungs is?

Ahydrogen sulphide
Bcarbon(ii)oxide
Cchlorine
Dsulphur(iv)oxide
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Question 288
jamb 2022

An organic functional group which can likely decolorize ammoniacal silver nitrate is?

Aalkene
Balkane
Calkyne
Dalkanol
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Question 289
jamb 2022

Zn + 2HCL → ZnCl\(_2\) + H\(_2\) 

What happens to zinc in the above reaction?

Aoxidized
Ba reactant
Creduced
Da metal
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Question 290
jamb 2022

N\(_2\)O\(_4\) ⇔ 2NO\(_2\)          (Δ = -ve)

From the reaction above, which of these conditions would produce the highest equilibrium yield for N\(_2\)O\(_4\)?

ALow temperature and high pressure
BLow temperature and low pressure
Chigh temperature and low pressure
Dhigh temperature and high pressure
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Question 291
jamb 2022

An organic compound with fishy smell is likely to have a general formula?

ARCONH\(_2\)
B
CRNH\(_2\)
DRCOR\(^1\)
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Question 292
jamb 2022

Using the metal activity series, the metal that can liberate hydrogen gas from steam is?

Airon
Bcopper
Ctin
Dlead
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Question 293
jamb 2022

Addition of charcoal to the filter bed of sand during water treatment for township supply is to?

Aprevent goiter
Bprevent tooth decay
Cremove odour
Dkill germs
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Question 294
jamb 2022

On the basis of the electrochemical series, which of these ions will show the greater tendency to be discharged at the cathode in an electrolytic cell

Acu\(^{2+}\)
Bsn\(^{2+}\)
Cfe\(^{2+}\)
Dzn\(^{2+}\)
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Question 295
jamb 2022

A chemical widely used as a fertilizer is?

Agalena
Bbauxite
Cemerald
Dnitrochalk
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Question 296
jamb 2022

Addition of sodium chloride to water to form a solution would  lead to?

Aincrease in freezing point and increase the boiling point
Bincrease in freezing point and decrease the boiling point
Cdecrease in freezing point and decrease the boiling point
Ddecrease in freezing point and increase the boiling point
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Question 297
jamb 2022

An organic compound which liberate carbon(iv)oxide from trioxocarbonate(iv) solution is likely to be?

AC\(_2\)H\(_5\)OH
BC\(_3\)H\(_4\)
CC\(_6\)H\(_6\)
DCH\(_3\)COOH
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Question 298
jamb 2022

The sulphide that is commonly used in coating electric fluorescent tubes is?

Airon(ii)Sulphide
Btin(ii)sulphide
CZinc Sulphide
Dlead(iv) Sulphide
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Question 299
jamb 2022

How many neutrons are present in atom with mass number and atomic number 37 and 17 respectively?

A18
B20
C37
D17
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Question 300
jamb 2022

The following non-metal form acidic oxides with oxygen except?

Aphosphorus
Bsulphur
Ccarbon
Dchlorine
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