2003 - JAMB Chemistry Past Questions and Answers - page 2
11
When cathode rays are deflected onto the electrode of an electrometer, the instrument becomes
A
negatively charged
B
positvely charged
C
neutral
D
bipolar
correct option: a
Users' Answers & Comments12
The weakest attractive force that can be observed between two molecules is
A
ionic
B
covalent
C
coordinate covalent
D
van der Waals
correct option: d
Users' Answers & Comments13
A consequence of global warming is
A
air pollution
B
water pollution
C
increased humudity
D
flooding
correct option: d
Users' Answers & Comments14
Which of the following ions is acidic?
A
K+
B
KNO3-
C
S2-
D
H3O+
correct option: b
Acids are ionic compounds ( a compound with a positive or negative charge) that break apart in water to form a hydrogen ion (H+).
For example: NaCl, KNO3, CaBr2, CsClO4
Users' Answers & CommentsFor example: NaCl, KNO3, CaBr2, CsClO4
15
The structural component that makes detergent dissolve more quickly in water than soap is
A
-SO3- Na+
B
-COO-Na-
C
-SO4- Na+
D
-COO-K+
correct option: a
Users' Answers & Comments16
A liquid that will dissolve fat is
A
Hydrochloric acid
B
Calcium hydroxide
C
Kerosene
D
Water
correct option: b
Users' Answers & Comments17
What mass of K2CrO4 is required to prepare 250cm3 of 0.020 mol dm3 solution?
[K2CrO4 = 194.2g mol-1]
[K2CrO4 = 194.2g mol-1]
A
0.97g
B
9.70g
C
19.42g
D
97.10g
correct option: a
1 mole m-3 K2CrO4 contains 194.2g mol-1 in 1000cm3
1 mole m-3 K2CrO4 contains 92.2g mol-1 in 500cm3
1 mole m-3 K2CrO4 contains 48.55g mol-1 in 250cm3
If n molm-3 K2CrO4 contain 48.55
0.02 molm-3 will contain (0.02/1) * (48.55/1) = 0.97g
Users' Answers & Comments1 mole m-3 K2CrO4 contains 92.2g mol-1 in 500cm3
1 mole m-3 K2CrO4 contains 48.55g mol-1 in 250cm3
If n molm-3 K2CrO4 contain 48.55
0.02 molm-3 will contain (0.02/1) * (48.55/1) = 0.97g
18
Farmlands affected by crude-oil spillage can be decontaminated by
A
Adding acidic solution
B
Using aerobic bacteria
C
Pouring water on the affected water area
D
Burning off the oil from the area
correct option: b
Users' Answers & Comments19
When 10g of sodium hydroxide is dissolved in 1000cm3 of water, the sodium formed is approximately
[Na = 23, H = 1, O = 16]
[Na = 23, H = 1, O = 16]
A
0.01 mol dm-3
B
0.10 mol dm-3
C
0.25 mol dm-3
D
0.50 mol dm-3
correct option: c
Users' Answers & Comments20
A change in temperature of a saturated solution disturb the equilibrium between the
A
Dissolved solute and the solvent
B
Solvent and undissolved solute
C
Dissolved solute and undissolved solute
D
Dissolved solute and the solution
correct option: c
Users' Answers & Comments