What volume of oxygen is produced from the decomposition of 2 mole of KCIO3 at s.t.p?
[Molar volume of a gas at s.t.p = 22.4 dm3]
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(D)
67.2 dm3
2
Which of the following is physical change?
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(B)
Freezing ice cream
3
What is the percentage by mass of oxygen in Al2(SO4)3. 2H2O?
[Al = 27, S = 32, H = 1, O = 16]
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(D)
59.25%
4
The filter in the cigarette reduces the nicotine content by
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(B)
Adsorption
5
3Cu + pHNO3 →3Cu(NO)2 + 4H2 O + xNO
In the equation above, the values of p and x respectively are
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(D)
8 and 2
6
Neutral atoms of neon with atomic number 10 have the same number of electron as
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(D)
Mg2+
7
The noble gases owe their inactivity to
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(A)
Octet configuration
8
According to the kinetic theory, an increase in temperature causes the kinetic energy of particles to
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(B)
Increase
9
I. H = 1S\(^1\) II. N = 1S\(^2\) 2S\(^2\)2P\(^3\) III. O = 1S\(^2\) 2S\(^2\) 2P\(^4\) IV. Zn = 1S\(^2\) 2S\(^2\) 2P\(^6\) 3S\(^2\) 3P\(^6\) 4S\(^2\) 3d\(^{10}\)
From the above, which of the following pairs is like to be paramagnetic?
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(B)
I and III
10
A gas exerts pressure on its container because
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(D)
the molecules of a gas collide with the walls of the container
11
When cathode rays are deflected onto the electrode of an electrometer, the instrument becomes
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(A)
negatively charged
12
The weakest attractive force that can be observed between two molecules is
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(D)
van der Waals
13
A consequence of global warming is?
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(D)
flooding
14
Which of the following ions is acidic?
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(D)
H3O+
15
The structural component that makes detergent dissolve more quickly in water than soap is
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(A)
-SO3- Na+
16
A liquid that will dissolve fat is?
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(C)
Kerosene
17
What mass of K2CrO4 is required to prepare 250cm3 of 0.020 mol dm3 solution?
[K2CrO4 = 194.2g mol-1]
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(A)
0.97g
18
Farmlands affected by crude-oil spillage can be decontaminated by
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(B)
Using aerobic bacteria
19
When 10g of sodium hydroxide is dissolved in 1000cm\(^3\) of water, the sodium formed is approximately
[Na = 23, H = 1, O = 16]
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(C)
0.25 mol dm-3
20
A change in temperature of a saturated solution disturb the equilibrium between the
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(C)
Dissolved solute and undissolved solute
21
If an equilibrium reaction has ΔH > 0, the reaction will proceed favourably in the forward direction at
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(A)
High temperature
22
The commonest feature of reactions at the anode is that
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(B)
oxidation is involved
23
Which of the following will change when a catalyst is added to a chemical reaction?
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(A)
The activation energy
24
If y is an oxidizing agent that reacts with a reducing agent, Z, which of the following is correct?
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(B)
Y becomes reduced
25
When at equilibrium, which of the reactions below will shift to the right if the pressure is increased and the temperature is kept constant?
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(C)
2H2(g) + O2(g) ↔ 2H2O(g)
26
In the electrolysis of a concentrated solution of sodium chloride using electrodes, which of the following ions are discharged at the cathode and anode respectively?
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(D)
H+ and Cl-
27
CO(g) + H2O(g) → CO2(g) + H2(g)
From the reaction above, calculate the standard enthalpies of formation if CO2(g), H2O(g) and CO(g) in kJ mol-1 are -394, -242, and -110 respectively.
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(B)
-42 kJ mol-1
28
When sugar is dissolved in tea, the reaction is always accomplished by
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(A)
positive change in entropy
29
Which of the following is an electrolyte?
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(B)
Sodium acetate solution
30
Chlorine gas is prepared in the laboratory by
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(A)
adding concentrated hydrochloric acid to solid manganese (IV) oxide
31
Metals of the first transition series have special properties which are different from those of groups I and II elements because they have partially filled
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(C)
d orbitals
32
Hydrogen can be displaced from a hot alkaline solution by?
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(D)
Sn
33
Which of the following statements is true of sulphur (IV) oxide?
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(C)
It is an acid hydride
34
The salt that will form a precipitate soluble in excess ammonia solution is
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(B)
Cu(NO3)2
35
The metal that liberates hydrogen from cold water in bubbles only is?
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(C)
Ca
36
Chlorine gas turns a damp starch-iodide paper
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(D)
dark blue
37
The modern process of manufacturing steel for iron is by
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(C)
blast reduction
38
Ethene reacts with hydrogen bromide to give
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(B)
CH3CH2Br
39
How many isomers does pentane have?
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(D)
3
40
The leachate of a certain plant ash is used in local soap making because it contains
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(C)
potassium hydroxide
41
The formula for ethyl butanoate is
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(A)
C3H7COOC2H5
42
The type of reaction that is peculiar to benzene is?
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(D)
substitution
43
Ethanol reacts with excess acidified K\(_2\)Cr\(_2\)O\(_7\) to produce
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(D)
ethanoic acid
44
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]
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(C)
C6H12O6
45
The process by which atoms are rearranged into different molecular structure in the petroleum refining process is referred to as
