2012 - JAMB Chemistry Past Questions and Answers - page 1
1
Which of the following methods can be used to obtain pure water from a mixture of sand, water and methanoic acid?
A
netralization with NaOHfoolowed by filtration
B
neutralization with NaOH followed by distillation
C
fractional distillation
D
filtration followed by distillation
correct option: d
Users' Answers & Comments2
How many atoms are present in 6.0g of magnesium?
[Mg = 24, NA = 6.02 x 1023 mol-1]
[Mg = 24, NA = 6.02 x 1023 mol-1]
A
1.20 x 1022
B
2.41 x 1022
C
1.51 x 1023
D
3.02 x 1023
correct option: c
Users' Answers & Comments3
50 cm3 of gas was collected over water at 10oC and 765 mm Hg. Calculate the volume of the gas at s.t.p. if the saturated vapour pressure of water at 10 oC is 5mm Hg
A
49.19 cm 3
B
48.87 cm 3
C
48.55 cm 3
D
48.23 cm 3
correct option: d
Users' Answers & Comments4
An increase in the pressure exerted on gas at a constant temperature results in
A
a decrease in the number of effective collisions
B
a decrease in volume
C
an increase in the average intermolecular distance
D
an increase in volume
correct option: b
Users' Answers & Comments5
2H2(g) + O2(g) → 2H2 O(g)
In the reaction above, what volume of hydrogen would be left over when 300 cm3 of oxygen and 1000 cm3 of hydrogen are exploded in a sealed tube?
In the reaction above, what volume of hydrogen would be left over when 300 cm3 of oxygen and 1000 cm3 of hydrogen are exploded in a sealed tube?
A
200 cm3
B
400 cm3
C
600 cm3
D
700 cm3
correct option: b
Users' Answers & Comments6
l . Evaporation. ll. Sublimation. lll. Diffusion. IV. Brownian motion.
Which of the above can correctly be listed as evidences for the particulate nature of matter?
Which of the above can correctly be listed as evidences for the particulate nature of matter?
A
I and lll only
B
ll and lV only
C
l, ll and lll only
D
l, ll, lll and lV
correct option: d
Users' Answers & Comments7
If the elements X and Y have atomic numbers 11 and 17 respectively, what type of bond can they form?
A
Dative
B
Covalent
C
Lonic
D
Metallic
correct option: c
Users' Answers & Comments8
A hydrogen atom which has lost an electron contains
A
one proton only
B
one neutron only
C
one proton and one neutron
D
one proton, one electron and one neutron
correct option: c
Users' Answers & Comments9
The electronic configuration of Mg 2+ is
A
ls 22s 22P 63s23P2
B
Is22s22P6
C
ls22s22p63s2
D
ls22s22P4
correct option: b
Users' Answers & Comments10
Group VII elements are
A
monoatmic
B
good oxidizing agents
C
highly electropositive
D
electron donors
correct option: b
Users' Answers & Comments