seperation of mixtures and purification of chemical substance Generix Content - seperation of mixtures and purification of chemical substance
HOME

EXAMS

JAMB

WAEC

CONTENTS

SIGN IN

JOIN NOW
"seperation of mixtures and purification of chemical substance" question number distribution across years
loading...
Search "seperation of mixtures and purification of chemical substance" on the following sites online
 
Chemistry index on skoool nigeria
 
JAMB questions for "Chemistry :: seperation of mixtures and purification of chemical substance"
Q1

Which Chemistry Question Paper is given to you?

A

Type A

B

Type B

C

Type C

D

Type D

E
Q2

Which of the following is an example of a mixture?

A

sand

B

washing soda

C

common salt

D

blood

E
Q3

A mixture of sugar and sulphur can be separated by

A

dissolution in water, evapouration and filteration

B

filteration, evapouration and dissolution in water

C

dissolution in water, filteration and evapouration

D

evapouration, dissolution in water and filteration

E
Q4

Which of the following is a physical change?

A

Freezing ice cream

B

Dissolving calcium in water

C

Burning kerosine

D

Exposing white phosphorous to air

E
Q5

The percentage of water of crystallization in ZnSO4.7H2O is

 

[Zn = 65, S = 32, O = 16, H = 1]

A

33%

B

44%

C

55%

D

87%

E
Q6

When sodium trioxocarbonate (IV) decahydrate loses its water of crystallization to the atmosphere, the process is

A

combustion of hydrocarbons

B

neutralization of an acid by a base

C

combustion of hydrogen

D

electrolysis of brine

E
Q7

Chlorophyll obtained from green leaves of plant can be shown to b composed by the technique of

A

crystallization

B

hydrolysis

C

chromatography

D

sublimation

E
Q8

In countries where the temperature falls below 273K, salt is always sprinkled on the icy roads in order to

A

lower the melting point of the ice

B

increase the density of the ice

C

make the ice improve

D

raise the melting point of the ice

E
Q9

Which of the following gives a precipitate when treated with NaOH soution?

A

haematite, malachite and limonite

B

chalcocite, calamine and bornite

C

magnetite, haematite and limonite

D

malachite, charcocite and bornite

E
Q10

A mixture of petrol and water can be separated through

A

the use of filter paper

B

the use of a separating funnel

C

centrifugation

D

distillation

E
Q11

The raw material used for the smelting of iron ore in a furnace is 

A

CaSO4

B

CaCO3

C

CuSO4

D

Zn(NO3)2

E
Q12

Group 1 A metals are not found free in nature because they

A

are very attractive and unstable

B

are malleable and ductile

C

have high melting and boiling points

D

conduct heat and electricity

E
Q13

In the diagram above, mixture Y is

A

NH4NO3(s) + CaSO4(s)

B

NH4Cl(s) + NaNO2(aq)

C

NH4NO2(s) + Na2SO4(s)

D

NH4Cl(s) + Ca(OH)2(s)

E
Q14
The order in which a mixture of sand, ammonium chloride and sodium chloride can be separated is
A
dissolution → dryness → filteration → evapouration
B
filteration → sublimation → evapouration → dryness
C
sublimation → dissolution → filteration → evapouration
D
dissolution → filteration → sublimation → evapouration
E
Q15
A heterogeneous mixture can be defined as any mixture
A
whose composition is uniform
B
whose composition is not uniform
C
formed by solids and liquids
D
of a solute and a solvent
E
Q16
Sugar is separated from its impurities by
A
distillation
B
evaporation
C
precipitation
D
crystallization
E
Q17
25 cm3 of a mixture of noble gases was obtained from air after the removal of other constituents. what was the original volume of air?
A
125 cm3
B
1 250 cm3
C
2 500 cm3
D
80 cm3
E
Q18
When a solid substance disappears completely as a gas on heating, the substances is said to have undergone.
A
sublimation 
B
crystallization
C
distillation
D
evapouration
E
Q19
In the diagram above, Y is
A
N2O5
B
NO
C
N2O4
D
NO2
E
Q20
The filter in a cigarette reduces the nicotine content by
A
adsorption 
B
absorption 
C
burning
D
evaporation
E
Q21
Which of the following is a physical change?
A
freezing ice-cream
B
Dissolving calcium in water
C
Burning kerosine
D
Exposing white phosphorous to air
E
Q22
The chromatographic separation of ink is based on the ability of the components to
A
react with the solvent
B
react with each other
C
dissolve in each other in the column
D
move at different speeds in the column
E
Q23
A little quantity of trichloromethane (b. pt. 600C) was added to a large quantity of ethanol (b. pt. 780C). The most probable boiling point of the resultant mixture is from
A
690C - 700C
B
700C - 740C
C
820C - 840C
D
600C - 780C
E
Q24
A mixture of iodine and sulphur crystals can be separated by treatment with
A
water to filter off sulphur
B
carbon  (IV) sulphide to filter off iodine
C
ethanoic acid to filter off sulphur
D
methanol to filter off iodine
E
Q25
Sieving is a technique used to separate mixtures containing solid particles of  
A
small sizes
B
large sizes
C
different sizes
D
the same size
E
Q26
which of the following compounds is composed of Al, Si, O and H?
A
Epsom salt
B
Limestone 
C
Clay
D
Urea
E
Q27
In the diagram above, the mixture of the two solids P and Q can be separated by
A
distillation
B
fractional distillation
C
crystallization
D
fractional crystallization
E
Q28
The property used in obtaining oxygen and nitrogen industrially from air is the
A
boiling point
B
density
C
rate of diffusion
D
solubility
E
Q29
A mixture of iron and sulphur can be separated by dissolving the mixture in
A
steam
B
dilute hydrochloric acid
C
dilute sodium hydroxide
D
benzene
E
Q30
The section PQ indicates that X is
A
a mixture of salts
B
a hydrated salt
C
an ionic salt
D
pure compound
E
Q31
Chromatography is used to seperate components of mixtures which in their rates of
A
diffusion
B
migration
C
reaction
D
sedimentation
E
Q32
Which of the following is an example of a chemical change?
A
Dissolution of salt in water
B
Rusting of iron
C
Melting of ice
D
Separating a mixture by distillation
E
Q33
A mixture of sand, ammonium chloride and sodium chloride is best separated by
A
sublimation followed by addition of water and filteration.
B
sublimation followed by addition of water and evaporation
C
addition of water followed by filteration by filteration and sublimation
D
addition of water followed by crystallization and sublimation
E
Q34
A pure solid usually melts
A
over a wide range of temperature
B
over a narrow range of temperature
C
at a lower temperature than the impure one
D
at the same temperature as the impure one
E
Q35
A gaseous mixture of 80.0 g of oxygen 56.0g of nitrogen has a total pressure of 1.8 atm. The partial pressure of oxygen in the mixture is [O = 16, N = 14]
A
0.8 atm
B
1.0 atm
C
1.2 atm
D
1.4 atm
E
Q36
The dissolution of common salt in water is a physical change because
A
the salt can be obtained by crystallization
B
the salt can be recovered by the evaporation of the water
C
heat is not generated during mixing
D
the solution will not boil at 1000C
E
Q37
Which of the following substances is a mixture?
A
Sulphur powder
B
Bronze
C
Distilled water
D
Ethanol
E
Q38
Which of the following substances is not homogenous mixture?
A
Filtered sea water
B
Soft drink
C
Flood water
D
Writing ink
E
Q39
There is a large temperature interval between the melting point and the boiling point of a metal because
A
metals have very high melting points
B
metals conduct heat very rapidly
C
melting does not break the metallic bond
D
the crystal lattice of metals is easily broken
E
Q40
Which of the following can be obtained by fractional distillation?
A
Nitrogen from liquid air.
B
Sodium chloride from sea water.
C
Iodine from a solution of Iodine in carbon tetrachloride.
D
Sulphur from a solution of sulphur in carbon disulphide.
E
Q41
Which of the following are mixtures? I. Petroleum II. Rubber latex III. Vulcanizer's solution IV. Carbon (II) sulphide
A
I, II and III
B
I, II and IV
C
I and II
D
I and IV
E
Q42
Which of the following is a physical change?
A
The bubbling of chlorine into water
B
The bubbling of chlorine into a jar containing hydrogen
C
The dissolution of sodium chloride in water
D
The passing of steam over heted iron
E
Q43
The letters X, Y and Z respectively represents 
A
sublimation, condensation and freezing
B
sublimation, vapourisation, solidification
C
freezing, condensation and sublimation
D
evapouration, liquifaction and solidification
E
Q44
Which of the following would support the conclusion that a solid sample is a mixture?
A
The solid can be grouped to a fine powder.
B
The density of the solid is 2.25g dm-3.
C
The solid has a melting range of 3000C to 375oC
D
The solid absorbs moisture from the atomsphere.
E
Q45
It can be deduced from the vapour pressure curves above that
A
liquid I has the highest boiling point.
B
liquid II has the highest boiling point 
C
liquid III has the highest boiling point
D
liquid II has the lowest boiling point
E
Q46
The minimum volume of oxygen required for the complete combustion of a mixture of 10cm3 of CO and 15cm3 of H2
A
25.0 cm3
B
12.5 cm3
C
10.0 cm3
D
5.0 cm3
E
Q47
in the experiment above, ammonium chloride crystals deposit on the walls of the tube is as a result of
A
evaporation
B
recrystallization
C
sublimation
D
fractional precipitation
E
Q48
A brand of ink containing cobalt (II), copper (II) and Iron (II) ions can best be separated into various components by
A
fractional crystallization
B
fractional distillation
C
sublimation
D
chromatography
E
Q49
Which of the following substances is a mixture?
A
Granulated sugar
B
Sea water
C
Sodium chloride
D
Iron fillings
E
Q50
Which of the following substances has the lowest vapour density? [O = 16, Cl = 35.5, H = 1, C = 12]
A
Ethanoic acid
B
Propanol
C
Dichloromethane
D
Ethanal
E
Q51
The tabulated results below were obtained by titrating 10.0 cm3 of water with soap. The titration was repeated with the same sample of water after boiling.     Before boiling After boililg Final (cm3) 25.0 20.0 Initial (cm3) 0.0 15.0
A
1:5
B
1:4
C
4:1
D
5:1
E
Q52
In the course of an experiment, two gases X and Y were produced X turned wet lead ethanoate to black and Y bleached moist litmus paper. What are the elements(s) in each of the gases X and Y respectively?
A
H and S; Cl
B
H and O; Cl
C
H and S; C and O
D
H and Cl; S and O
E
Q53
Which of the following compounds would give lilac flame coloration and white precipitate with acidified barium chloride solution?
A
KCl
B
NaNO3
C
K2SO4
D
CaSO4
E
Q54
When ethanol is heated with excess concentrated sulphuric acid, the ethanol is
A
oxidized to ethene
B
polymerized to polyethene
C
dehydrated to ethene
D
dehydrated to ethyne
E
Q55
3.0 g of a mixture of potassium carbonate and potasium chloride were dissolved in a 250 cm3 standard flask. 25 cm3 of this solution required 40.00 cm3 of 0.1 MHCl for neutralization. What is the percentage by weight of K2CO3 in the mixture?   (K = 39, O = 16, C = 12)
A
60
B
72
C
82
D
89
E
92
Q56
Sodium chloride may be obtained from brine by
A
titration
B
decantation
C
distillation
D
evaporation
E
sublimation
Q57
Some copper (II) sulphate pentahydrate (CuSO4 5H2O), was heated at 1200C with following results: Wt of crucible = 10.00g; Wt of crucible + CuSO4 5H2O = 14.98g, Wt of crucible + residue = 13.54g. How many molecules of water of crystallization were lost?   (H = 1, Cu = 63.5, O = 16, S = 32)
A
1
B
2
C
3
D
4
E
5
Q58
A mixture contains 20 cm3 of hydrogen, 35 cm3 of oxygen, 15 cm3 of carbon monoxide and 10 cm3 of nitrogen at S.T.P. Which of the following gives the mole fraction of hydrogen in this mixture?
A
0.02
B
0.16
C
0.20
D
0.25
E
20
Q59
When a pressure cooker is half filled with water, and heated to boiling point, then the pressure inside the cooker will
A
decrease, since only a fraction of water molecules has changed to vapour.
B
remain constant, because the total number of molecules has not changed.
C
increase, because the water molecules can now reach every part of the sealed tube.
D
decrease, since water boils under reduced pressure.
E
increase, because the water vapour molecules now strike the walls of the tube more frequently because of their increased velocity.
Q60
The products of the reaction between dilute sulphuric acid and sodium thiosulphate crystals are
A
NaSO4 + SO2 + O2 + H2O
B
Na2SO3 + SO3 + O2 + H2O
C
Na2SO4 + SO2 + S + H2O
D
Na2SO4 + SO3 + S + H2O
E
Na2SO4 + SO2 + H2O only-