JAMB - Chemistry (2015)

1
The filter in the cigarette reduce the nicotine construct by
Answer
(B)
adsorption
2
Which of these require crystallization most?
Answer
(A)
Drug making
3
Iron is often galvanized in order to
Answer
(C)
Protect it against corrosion
4
In the industrial production of H2 from water gas the CO2 produced along with the H2 is removed by
Answer
(A)
washing under pressure
5
The gas that is most useful in protecting humans against solar marathon is
Answer
(B)
ozone
6
Vulcanization involve the removal of
Answer
(C)
the double bond
7
The acid in electrolysis of water is dilute
Answer
(C)
H2SO4
8
A small quantity of solid ammonium chloride (NH4Cl) heated gently in a test tube, the solid gradually disappear produce two gases. Later, a white cloudy deposit was absence on the cooler part of the test tube. The ammonium chloride is to have undergo
Answer
(B)
sublimation
9
When salt loses its water of crystallization to the atmosphere on exposure, the process is said to be
Answer
(A)
efflorescence
10
Atomicity of ozone is
Answer
(C)
3
11
Which of the noble gases has the greatest ionization energy
Answer
(A)
He
12
The weakest attractive force that can be observed between two molecules is
Answer
(D)
vander Waals
13
An elements used in production of matches is
Answer
(D)
sulphur
14
Cathode rays cause an object placed behind a perforated anode to cast a shadow on the screen. This observation shows that the rays
Answer
(D)
travel in straight lines
15
Flow of current in electrolytes is due to the movement of
Answer
(C)
Ions
16
A suitable reagent for distinguish between ethanoic and ethanol is
Answer
(C)
sodium hydrogen trioxocarbonate (iv)
17
The above orbital diagram shown the electronic configuration of
Answer
(B)
nitrogen
18
Which of the following metals burns with brick red
Answer
(B)
Ca
19
In the production of soap, concentrated sodium chloride solution is added to
Answer
(B)
decrease the solubility of the soap
20
A liquid that will dissolve fat is
Answer
(C)
kerosene
21
Tartaric acid is used industrially to
Answer
(A)
make baking powder
22
P1V1 = P2V2 supports ?
Answer
(B)
Boyles’s law
23
A fixed mass of gas occupies 92cm3 at 3°C. What will be its volume at 18C if the pressure remains constant?
Answer
(D)
97.0cm3
24
Which of the following ions  requires the largest quantity of electricity for discharge at an electrode?
Answer
(A)
2.0 mole of Q3+
25
Hydrogen can be displaced from a hot alkaline solution by
Answer
(D)
Sn
26
Which of the following types of alkanols undergo oxidation to produce alkanoic acids.

I. Primary alkanols
II. Secondary alkanols
III. Tertiary alkanols
Answer
(D)
I only
27
Rare gases are stable because they
Answer
(C)
have duplet or octet electronic configuration in the outermost shells in their atoms
28
A major source of oxide of nitrogen is from the burning of
Answer
(C)
fuel
29
Which of these radioactive elements is commonly used as a nuclear fuel
Answer
(A)
uranium
30
All these are electromagnetic waves except
Answer
(B)
Photon
31

\(Cu_2S_{(s)}+ O_{2(g)} = 2CU_{(s)} + SO_{2(g)}\).

In the above reaction, the oxidation number of Cu changes from ___ to _______?

Answer
(A)
+1 to 0
32
The number of isomers formed by C6H14 is
Answer
(B)
5
33
The basic particles from which matter could be made up of are as follow, except?
Answer
(A)
Salt
34
The energy value of petrol can be determined by
Answer
(A)
Bomb calorimeter
35
What volume of 0.5mldm3 H2SO4 will exactly neutralize 20cm3 of 0.1moldm3 NaOH Solution?
Answer
(A)
2.0cm3
36
A compound contains 40.0% carbon, 6.7% hydrogen and 53.3% oxygen. If the molar mass of the compound is 180, Find the molecular formula [H = 1, C = 12, O = 16)
Answer
(C)
C6H12O6
37
An oxidation state of Cr in K2Cr2O7
Answer
(B)
6
38
The elements that belong to the third period of periodic table are
Answer
(D)
Na, Mg, S and Ar
39
When sugar is dissolve in tea, the reaction is accomplished by?
Answer
(C)
no entropy change
40
NH3(g) + HCl(s) → NH 4Cl (s)

The entropy change in the system above is
Answer
(C)
negative
41
Detergents are manufactured with straight hydrocarbon chains, is to make them
Answer
(B)
biodegradable
42
Which of the following results in the fall of acid rain?
Answer
(C)
oxides of sulphur
43
The furring of kettles is caused by the presence of what compound in water?
Answer
(D)
calcium trioxocarbonate (IV)
44
A difference between chemical and physical change is that in a chemical change
Answer
(D)
a new substance is formed
45
According to the kinetic theory an absence in temperature causes the kinetic energy of particles to
Answer
(D)
be zero
46
PCL5(g)= PCL3(g) + Cl2(g)

In the reaction above, a decrease in pressure will
Answer
(B)
Increase yield of Pcl3
47
Which of the following gives a precipitation when treated with NaOH Solution?
Answer
(A)
AlCl3
48
Electronic configuration of an element 13 in the subsidiary energy level is
Answer
(A)
\( 1s^2 2s^2 2p^6 3s^2 3p^1 \)
49
Alloys are best prepared by
Answer
(D)
cooking a molten of the metals
50
In countries where the temperature fall below 273k, salt always spilled on the road in order to
Answer
(D)
reduce the freezing point of ice
51
The substance that is used in the steel industry for the removal of carbon. Sulphur and phosphorus impurities from pig iron is
Answer
(A)
oxygen
52
If glucose is heated with concentrated tetraoxosulphate(vi)acid, it will be dehydrated to?
Answer
(A)
carbon
53
Which of the following compounds can be represented by the molecular formula C2 H6O?
Answer
(B)
ethanol
54
what is the pH of 0.00lmoldm3 solution of sodium hydroxide
Answer
(D)
11
55
N2O4(g)→ 2NO2(g)

In the endothermic reaction above, more products formed will be favored by
Answer
(C)
a decrease pressure
56
Chlorine gas turns damp starch-iodide paper
Answer
(D)
dark blue
57
Chlorine consisting of two isotope of mass number 35 and 37 in the ratio 3:1 has an atomic mass of 35.5. Calculate the relative abundance of the isotope of mass number 37
Answer
(B)
25
58
The principal constituent of natural gas is
Answer
(A)
methane
59
In the electrolysis of CuSo4(g) using platinum electrode the reaction at the anode is
Answer
(B)
4OH= 4e- + 2H2O + O2
60
S block elements of the periodic table one made up of
Answer
(B)
groups 1, and 2