Which of the following instruments is used in detecting the presence of radiation?
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(B)
Geiger-Muller counter
2
The molecule which has a linear shape is
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(D)
CO2
3
The formula of the compound formed between a trivalent metal, M and a divalent non-metal, Y is
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(A)
M2Y3
4
An atom of an element X gains two electrons. The symbol of the ion formed is
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(C)
X 2-
5
Which of the following statements is correct?
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(D)
Cations are smaller than the parent atom
6
Which of the following arrangements represents the correct order of electronic energy level?
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(C)
1s 2s 2p 3s 3p 4s 3d
7
The element with electron configuration 1s\(^2\) 2s\(^2\) 2p\(^6\) 3s\(^2\) 3p\(^1\) belongs to
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(D)
p-block, period 3, group 3
8
In the periodic table all elements within the same group have the same
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(B)
number of valence electrons
9
Which of the following halogens is liquid at room temperature?
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(C)
Bromine
10
Rare gases are stable because they
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(D)
have octet structures
11
In the periodic table, alkaline earth metals can be found in group
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(B)
ll
12
In which of the following series are the atoms arranged in order of increasing ionization energy?
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(C)
O, F, Ne
13
Which of the following bond types is responsible for the high boiling point of water?
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(D)
Hydrogen bond
14
In metallic solid, the forces of attraction is between the mobile valence electrons and the
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(D)
positively charged nuclei
15
The bonds in crystalline ammonium chloride are
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(C)
ionic, covalent and dative
16
Which of the following elements is diatomic?
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(B)
Oxygen
17
Noble gas molecules are held together by
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(A)
van der Waals forces
18
Which of the following statements about nuclear reaction is correct? The reaction
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(B)
takes place inside the nucleus
19
Consider the reaction represented by the following equation: C\(_2\)H\(_2\) + yH\(_2\) → C\(_2\)H\(_6\). The value of y in the reaction is
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(C)
2
20
The volume of 0.25 moldm-3 solution of KOH that would yield 6.5g of of solid KOH on evaporation is (K = 39.0; o = 16.0; H = 1.00)
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(A)
464.30 cm3
21
The percentage by mass of calcium in Ca(OCI)2 is [Ca = 40.0; CI = 35.5; O = 16.0]
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(A)
28.0%
22
The gas law which describes the relationship between volume and temperature is
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(B)
Charles' law
23
Which of the following phenomenna lead to decrease in volume of a liquid in an open container?
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(C)
Evaporation
24
The pressure exerted by a gas is a function of the
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(D)
frequency of collision between gaseous molecules
25
Which of the following gases are arranged in increasing order of diffusion rate? [H = 1 .0; C = 12; N = 14; O = 16; S = 32]
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(A)
SO 2 O2, NH3 H2
26
Which of the following variables is a measure of the average kinetic energy of the molecule of a gas?
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(C)
Temperature
27
When heat is absorbed during a chemical reaction, the reaction is said to be
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(B)
endothermic
28
The aqueous solution which has pH > 7 is
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(D)
Na2CO3(aq)
29
Which of the following acids would readily react with CaCO3 to liberate CO2?
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(B)
H2SO4
30
Which of the following compounds crystallizes without water of crystallization?
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(C)
NaCI
31
A substance is said to be impure if
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(A)
its melting point range is wide
32
The following factors affect the solubility of a solid in a given solvent except
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(C)
pressure
33
Consider the reaction represented by the equation: N\(_2\)O\(_4\)(g) ⇌ 2NO\(_2\)(g) ; ∆H = + x kJmol-1
What happens when the temperature is reduced at equilibrium?
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(B)
Concentration of N 2O4(g) increases.
34
Which of the following cells produce electrical energy from chemical reactions?
l. Lead-acid battery ll. Dry cell III. Deniell cell IV Electrolytic cell
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(B)
l, ll, and III only
35
Consider the redox reaction as represented by the following equation: 12(aq) + 2S2O32-(aq) → 21-(aq) + S4O62-(aq). Which of the species in the equation is reduced?
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(C)
12(aq)
36
The separation of petroleum fractions depends on the differences in their
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(D)
boiling points
37
The major product formed by the reaction between ethanoic acid and aqueous sodium hydroxide is
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(B)
sodium ethanoate
38
Which of the following organic compounds would decolourize bromie water?
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(A)
Benzene
39
How many isomers has C\(_3\)H\(_6\)CI\(_2\)?
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(C)
4
40
Which of the following reactions is common to all hydrocarbones?
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(A)
Combustion
41
A hydrocarbon compound contains 92.3% carbon Determine its empirical formula [H = 1.00; C = 12.0]
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(A)
CH
42
The main function of limestone in the blast furnace is to
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(C)
remove impurity
43
Which of the following raw materials is used in a plastic industry?
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(A)
Ethene
44
Which of the following statements about fine chemical is correct? It
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(C)
is produced in relatively small amount
45
Which of the following materials is classified as a non-biodegradable pollutant?
