2006 - JAMB Chemistry Past Questions and Answers - page 4
31
A decrease in atomic size and an increase in nuclear charge across a period lead to
A
an increase in the tendency to lose electron
B
an increase in chemical reactivity
C
a decrease in electropositivity
D
a decrease in covalency in bond formation
correct option: b
Users' Answers & Comments32
The order in which a mixture of sand, ammonium chloride and sodium chloride can be separated is
A
dissolution → dryness → filtration → evaporation
B
filtration → sublimation → evaporation → dryness
C
sublimation → dissolution → filtration → evaporation
D
dissolution → filtration → sublimation → evaporation
correct option: c
Users' Answers & Comments33
The idea of planetary electron was that of
A
Rutherford
B
Thompson
C
Bohr
D
Dalton
correct option: a
Users' Answers & Comments34
If 30cm3 of gas at 50oC is warmed to 80o at a fixed pressure, the fractional increase in volume is
A
0.009
B
0.093
C
0.910
D
1.090
correct option: d
Users' Answers & Comments35
2C2H2(g) + 5O2(g) → 4CO2(g) + 2H2O(g)
In the reaction above, the mass of carbon(IV)oxide produced on burning 78 g of ethyne is
[C =12, O = 16, H = 1]
In the reaction above, the mass of carbon(IV)oxide produced on burning 78 g of ethyne is
[C =12, O = 16, H = 1]
A
264 g
B
39 g
C
352 g
D
156 g
correct option: a
Users' Answers & Comments36
The ion that can be used as an oxidizing agent is
A
Au3+
B
Fe3+
C
F-
D
Ca2+
correct option: c
Users' Answers & Comments37
H2(g) + Br2(g) → 2HBr(g)
The above reaction is carried out at 25oC. ΔH is -72 kJ mol-1 and ΔS is - 106 J mol-1K-1, the reaction will
The above reaction is carried out at 25oC. ΔH is -72 kJ mol-1 and ΔS is - 106 J mol-1K-1, the reaction will
A
not proceed spontaneously at the given
B
proceed spontaneously at the given temperature
C
proceed in the reverse direction at the given temperature
D
proceed spontenously at lower temperature
correct option: a
Users' Answers & Comments38
Zinc and carbon rods are used as anode and cathode respectively in a
A
Leclanche cell
B
lead accumulator
C
Daniel cell
D
voltaic cell
correct option: a
Users' Answers & Comments39
The solution that will conduct the highest amount of electricity is
A
0.5 mol dm-3 of hydrochloric acid
B
2.0 mol dm-3 of hydrochloric acid
C
0.5 mol dm-3 ethanoic acid
D
2.0 mol dm-3 ethanoic acid
correct option: a
Users' Answers & Comments40
In which of the following is the oxidation number of sulphur equal to -2?
A
SO3
B
S8
C
H2S
D
SO2
correct option: c
Users' Answers & Comments