Chemistry Past Questions

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

40 questions
Question 1 of 20 40 total questions
Question 11
jamb 2020

The shape of ammonia molecule is?

ATrigonal planar
BOctahedral
CSquare planar
DTetrahedral
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Question 12
jamb 2020

Which of the following gases will rekindle a brightly splint?

A
BNO
CN\(_2\)O
DCL\(_2\)
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Question 13
jamb 2020

The volume occupied by 1.58g of a gas at S.T.P is 500cm\(^3\). What is the relative molecular mass of the gas?  [ G.M.V at S.T.P = 22.4dm\(^{3}\) ]

A28
B32
C44
D71
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Question 14
jamb 2020

The number of molecules of Carbon(iv)Oxide produced when 10.0g of CaCO\(_3\) is treated with 0.2dm\(^3\) of 1 Mole of HCL in the equation

CaCO\(_3\) + 2HCL ⇒  CaCl\(_2\)  + H\(_2\) O + CO\(_2\)  , is?

A1.00 X 10\(^{23}\)
B6.02 X 10\(^{23}\)
C6.02 X 10\(^{22}\)
D6.02 X 10\(^{24}\)
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Question 15
jamb 2020

How many valence electrons are contained in the element \(^{31}_{15}P\)?

A3
B4
C15
D31
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Question 16
jamb 2020

The products of the thermal decomposition of ammonium trioxonitrate(v) are?

ANitrogen (I) Oxide and Water
BAmmonia and Oxide
CNitrogen and Water
DNitrogen (IV) Oxide and Water
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Question 17
jamb 2020

Four elements P, Q, R and S have atomic numbers of 4, 10, 12 and 14 respectively. Which of these elements is noble gas? 

AP
BQ
CR
DS
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Question 18
jamb 2020

If the quantity of oxygen occupying 2.76L container at a pressure of 0.825 atm and 300k is reduced by one-half, what is the pressure exerted by the remaining gas?

A1.650atm
B0.825atm
C0.413atm
D0.275atm
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Question 19
jamb 2020

Which of the following substances is a mixture?

AGranulated sugar
BSeawater
CSodium chloride
DIron filling
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Question 20
jamb 2020

When water drops are added to calcium carbide in a container and the gas produced is passed through a jet and lighted, the resultant flame is called an?

AOxyethene
BOxyhydrocarbon flame
COxyacetylene flame
DOxymethane flame
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Question 21
jamb 2020

Liquid black soap is made by boiling palm oil with liquid extract of ash. The function of the ash is to provide the ?

AAcid
BEster of alkanoic acid
CAlkanol
D
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Question 22
jamb 2020

What process would coal undergo to give coal gas, coal tar, ammoniacal liquor and coke?

ASteam distillation
BDestructive distillation
CLiquefication
DHydrolysis
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Question 23
jamb 2020

What are the possible oxidation numbers of an element if its atomic number is 17?

A-1 and 7
B-1 and 6
C-3 and 5
D-2 and 6
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Question 24
jamb 2020

Which of the gas laws does this graph illustrate?

ABoyle
BCharles
CGay-Lussac
DGraham
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Question 25
jamb 2020

The best treatment for a student who accidentally poured conc tetraoxosulphate(vi) on his skin in the laboratory is to wash his skin with?

Awith cool running water
Bsodium hydroxide solution
Ciodine solution
Dsodium trioxonitrate(v) solution
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Question 26
jamb 2020

8g of CH\(_4\) occupies 11.2 at S.T.P. What volume would 22g of CH\(_3\)CH\(_2\)CH\(_3\) occupy under the same condition?

A3.7dm\(^3\)
B11.2dm\(^3\)
C22.4dm\(^3\)
D33dm\(^3\)
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Question 27
jamb 2020

An example of a polysaccharide is?

ADextrose
BMannose
CGlucose
DStarch
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Question 28
jamb 2020

Duralumin consists of aluminum, copper?

AZinc and Gold
BLead and Manganese
CNickel and Silver
DManganese and Magnesium
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Question 29
jamb 2020

Which of the following can be obtained by fractional distillation? 

ANitrogen from liquid air
BSodium Chloride from sea water
CIodine from solution of Iodine in carbon tetrachloride
DSulphur from the solution of sulphur in carbon disulphide
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Question 30
jamb 2020

The electronic configuration of an element is 1S\(^2\) 2S\(^2\) 2P\(^6\) 3S\(^2\) 3P\(^3\). How many unpaired electrons are there in the element?

A5
B4
C3
D2
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