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]
Одговорити
(D)
67.2 dm3
2
Which of the following is physical change?
Одговорити
(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]
Одговорити
(D)
59.25%
4
The filter in the cigarette reduces the nicotine content by
Одговорити
(B)
Adsorption
5
3Cu + pHNO3 →3Cu(NO)2 + 4H2 O + xNO
In the equation above, the values of p and x respectively are
Одговорити
(D)
8 and 2
6
Neutral atoms of neon with atomic number 10 have the same number of electron as
Одговорити
(D)
Mg2+
7
The noble gases owe their inactivity to
Одговорити
(A)
Octet configuration
8
According to the kinetic theory, an increase in temperature causes the kinetic energy of particles to
Одговорити
(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?
Одговорити
(B)
I and III
10
A gas exerts pressure on its container because
Одговорити
(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
Одговорити
(A)
negatively charged
12
The weakest attractive force that can be observed between two molecules is
Одговорити
(D)
van der Waals
13
A consequence of global warming is?
Одговорити
(D)
flooding
14
Which of the following ions is acidic?
Одговорити
(D)
H3O+
15
The structural component that makes detergent dissolve more quickly in water than soap is
Одговорити
(A)
-SO3- Na+
16
A liquid that will dissolve fat is?
Одговорити
(C)
Kerosene
17
What mass of K2CrO4 is required to prepare 250cm3 of 0.020 mol dm3 solution?
[K2CrO4 = 194.2g mol-1]
Одговорити
(A)
0.97g
18
Farmlands affected by crude-oil spillage can be decontaminated by
Одговорити
(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]
Одговорити
(C)
0.25 mol dm-3
20
A change in temperature of a saturated solution disturb the equilibrium between the
Одговорити
(C)
Dissolved solute and undissolved solute
21
If an equilibrium reaction has ΔH > 0, the reaction will proceed favourably in the forward direction at
Одговорити
(A)
High temperature
22
The commonest feature of reactions at the anode is that
Одговорити
(B)
oxidation is involved
23
Which of the following will change when a catalyst is added to a chemical reaction?
Одговорити
(A)
The activation energy
24
If y is an oxidizing agent that reacts with a reducing agent, Z, which of the following is correct?
Одговорити
(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?
Одговорити
(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?
Одговорити
(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.
Одговорити
(B)
-42 kJ mol-1
28
When sugar is dissolved in tea, the reaction is always accomplished by
Одговорити
(A)
positive change in entropy
29
Which of the following is an electrolyte?
Одговорити
(B)
Sodium acetate solution
30
Chlorine gas is prepared in the laboratory by
Одговорити
(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
Одговорити
(C)
d orbitals
32
Hydrogen can be displaced from a hot alkaline solution by?
Одговорити
(D)
Sn
33
Which of the following statements is true of sulphur (IV) oxide?
Одговорити
(C)
It is an acid hydride
34
The salt that will form a precipitate soluble in excess ammonia solution is
Одговорити
(B)
Cu(NO3)2
35
The metal that liberates hydrogen from cold water in bubbles only is?
Одговорити
(C)
Ca
36
Chlorine gas turns a damp starch-iodide paper
Одговорити
(D)
dark blue
37
The modern process of manufacturing steel for iron is by
Одговорити
(C)
blast reduction
38
Ethene reacts with hydrogen bromide to give
Одговорити
(B)
CH3CH2Br
39
How many isomers does pentane have?
Одговорити
(D)
3
40
The leachate of a certain plant ash is used in local soap making because it contains
Одговорити
(C)
potassium hydroxide
41
The formula for ethyl butanoate is
Одговорити
(A)
C3H7COOC2H5
42
The type of reaction that is peculiar to benzene is?
Одговорити
(D)
substitution
43
Ethanol reacts with excess acidified K\(_2\)Cr\(_2\)O\(_7\) to produce
Одговорити
(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]
Одговорити
(C)
C6H12O6
45
The process by which atoms are rearranged into different molecular structure in the petroleum refining process is referred to as
