2005 - JAMB Chemistry Past Questions and Answers - page 3
21
The solubility curve shows the variation of solute concentration with
A
volume
B
temperature
C
vapour density
D
pressure
correct option: b
Users' Answers & Comments22
The air around smelting industries is likely to contain
A
H2S, CO and N2
B
CO2, SO3 and H2
C
H2, SO2 and CO2
D
SO2, N2 and CO2
correct option: c
Users' Answers & Comments23
Kerosine is commonly used to remove the red colour stain of palm oil from cloths because it
A
helps to spread the oil over a larger surface area
B
react with the oil to form an odourless compound
C
makes the oil evaporate easily by dissolving it
D
helps to dilute the oil and reduce its colour
correct option: c
Users' Answers & Comments24
The gas that is the most dangerous pollutant to human is
A
sulphur (IV) oxide
B
carbon (IV) oxide
C
nitrogen (II) oxide
D
hydrogen sulphide
correct option: d
Users' Answers & Comments25
Natural water collected from rivers and ponds contain oxygen, carbon (IV) oxide and
A
nitrogen
B
hydrogen
C
chlorine
D
sulphur
correct option: a
Users' Answers & Comments26
How many moles of limestone will be required to produce 5.6g of CaO?
[Ca = 40, C = 12, O= 16]
[Ca = 40, C = 12, O= 16]
A
0.20 mol
B
0.10 mol
C
1.12 mol
D
0.56 mol
correct option: b
CaCO3 → CaO + CO2
CaCO3 = 40 + 12 + 16 * 3 = 100, CaO = 40 + 16 = 56
56gt of CaO was produced by 100g of CaCO3
∴ 5.6g of CaO will produce by
(5.6 * 100)/56 = 10g of CaCO3
moles = mass/molar mass = 10/100 = 0.10m
Users' Answers & CommentsCaCO3 = 40 + 12 + 16 * 3 = 100, CaO = 40 + 16 = 56
56gt of CaO was produced by 100g of CaCO3
∴ 5.6g of CaO will produce by
(5.6 * 100)/56 = 10g of CaCO3
moles = mass/molar mass = 10/100 = 0.10m
27
The shape of the hydrocarbon compound CH4 is
A
square planar
B
planar
C
linear
D
tetrahedral
correct option: d
Users' Answers & Comments28
Which of these properties gives a solid its definite shape?
A
strong intermolecular attraction
B
high melting point
C
high boiling point
D
weak intermolecular attraction
correct option: a
Users' Answers & Comments29
Sugar is separated from its impurities by
A
precipitation
B
crystallization
C
distillation
D
evaporation
correct option: b
Users' Answers & Comments30
The component of an atom that contributes least to its mass is the
A
proton
B
nucleus
C
neutron
D
electron
correct option: d
Users' Answers & Comments