2001 - JAMB Chemistry Past Questions and Answers - page 2
11
Deliquescent substance are used for
A
Cooling
B
Wetting
C
Melting
D
Drying
correct option: d
Users' Answers & Comments12
Pure solvents are obtained by
A
Distillation
B
Condensation
C
Extraction
D
Evaporation
correct option: a
Users' Answers & Comments13
What is the decrease in volume of air when pyrogallol is shaken with 30.00cm3 of air ?
A
15.00cm3
B
6.30cm3
C
0.63cm3
D
0.06cm3
14
Environmental pollution is worsened by the release from automobile exhausts of
A
Water vapour
B
Steam
C
Smoke
D
Heavy metals
correct option: c
Users' Answers & Comments15
The chemical used for coagulation in water purification is
A
Aluminium tetraoxosulphate (VI)
B
Copper tetraoxosulphate (VI)
C
Sodium tetraoxosulphate (VI)
D
Calcium tetraoxosulphate (VI)
correct option: a
Users' Answers & Comments16
Phosphorus is stored under water to prevent it from
A
Dehydrating
B
Becoming inert
C
Smelling
D
Catching fire
correct option: d
Users' Answers & Comments17
In which of the following reactions does reduction takes place
A
Fe2+ - e- → Fe3+
B
2O2- →O2 + 4e-
C
Cr – 2e- → Cr2+
D
2H+ + 2e- → H2
correct option: d
Users' Answers & Comments18
P(g) + Q(g) ↔ 3R(s) + S(g) ΔH is negative
Which of the following will increase the yield of R?
Which of the following will increase the yield of R?
A
Using a larger close vessel
B
Increasing the temperature
C
Removing some S
D
Adding a positive catalyst
correct option: c
Users' Answers & Comments19
A metal M displaces zinc from zinc chloride solution. This shows that
A
M is more electronegative than zinc
B
Zinc is above hydrogen in the series
C
M is more electropositive than zinc
D
Electrons flow from zinc to M
correct option: c
Users' Answers & Comments20
Which of the following best explains the increase in the rate of a chemical reaction as the temperature rises?
A
The bonds in the reacting molecules are more readily broken
B
The molecular collisions become more violent
C
A lower proportion of the molecules has the necessary minimum energy to react
D
The collision frequency of the molecules increase
correct option: d
Users' Answers & Comments