Which of the following instruments is used in detecting the presence of radiation?
Trả lời
(B)
Geiger-Muller counter
2
The molecule which has a linear shape is
Trả lời
(D)
CO2
3
The formula of the compound formed between a trivalent metal, M and a divalent non-metal, Y is
Trả lời
(A)
M2Y3
4
An atom of an element X gains two electrons. The symbol of the ion formed is
Trả lời
(C)
X 2-
5
Which of the following statements is correct?
Trả lời
(D)
Cations are smaller than the parent atom
6
Which of the following arrangements represents the correct order of electronic energy level?
Trả lời
(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
Trả lời
(D)
p-block, period 3, group 3
8
In the periodic table all elements within the same group have the same
Trả lời
(B)
number of valence electrons
9
Which of the following halogens is liquid at room temperature?
Trả lời
(C)
Bromine
10
Rare gases are stable because they
Trả lời
(D)
have octet structures
11
In the periodic table, alkaline earth metals can be found in group
Trả lời
(B)
ll
12
In which of the following series are the atoms arranged in order of increasing ionization energy?
Trả lời
(C)
O, F, Ne
13
Which of the following bond types is responsible for the high boiling point of water?
Trả lời
(D)
Hydrogen bond
14
In metallic solid, the forces of attraction is between the mobile valence electrons and the
Trả lời
(D)
positively charged nuclei
15
The bonds in crystalline ammonium chloride are
Trả lời
(C)
ionic, covalent and dative
16
Which of the following elements is diatomic?
Trả lời
(B)
Oxygen
17
Noble gas molecules are held together by
Trả lời
(A)
van der Waals forces
18
Which of the following statements about nuclear reaction is correct? The reaction
Trả lời
(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
Trả lời
(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)
Trả lời
(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]
Trả lời
(A)
28.0%
22
The gas law which describes the relationship between volume and temperature is
Trả lời
(B)
Charles' law
23
Which of the following phenomenna lead to decrease in volume of a liquid in an open container?
Trả lời
(C)
Evaporation
24
The pressure exerted by a gas is a function of the
Trả lời
(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]
Trả lời
(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?
Trả lời
(C)
Temperature
27
When heat is absorbed during a chemical reaction, the reaction is said to be
Trả lời
(B)
endothermic
28
The aqueous solution which has pH > 7 is
Trả lời
(D)
Na2CO3(aq)
29
Which of the following acids would readily react with CaCO3 to liberate CO2?
Trả lời
(B)
H2SO4
30
Which of the following compounds crystallizes without water of crystallization?
Trả lời
(C)
NaCI
31
A substance is said to be impure if
Trả lời
(A)
its melting point range is wide
32
The following factors affect the solubility of a solid in a given solvent except
Trả lời
(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?
Trả lời
(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
Trả lời
(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?
Trả lời
(C)
12(aq)
36
The separation of petroleum fractions depends on the differences in their
Trả lời
(D)
boiling points
37
The major product formed by the reaction between ethanoic acid and aqueous sodium hydroxide is
Trả lời
(B)
sodium ethanoate
38
Which of the following organic compounds would decolourize bromie water?
Trả lời
(A)
Benzene
39
How many isomers has C\(_3\)H\(_6\)CI\(_2\)?
Trả lời
(C)
4
40
Which of the following reactions is common to all hydrocarbones?
Trả lời
(A)
Combustion
41
A hydrocarbon compound contains 92.3% carbon Determine its empirical formula [H = 1.00; C = 12.0]
Trả lời
(A)
CH
42
The main function of limestone in the blast furnace is to
Trả lời
(C)
remove impurity
43
Which of the following raw materials is used in a plastic industry?
Trả lời
(A)
Ethene
44
Which of the following statements about fine chemical is correct? It
Trả lời
(C)
is produced in relatively small amount
45
Which of the following materials is classified as a non-biodegradable pollutant?
