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