Copper metal will react with concentrated trioxonitrate (V) acid to give?
คำตอบ
(D)
Cu(NO3)2 + 2NO2 + 2H2O
2
Which of the following separation is routinely applied in the petroleum industry
คำตอบ
(E)
Fractional distillation
3
Starch undergoes complete hydrolysis to produce
คำตอบ
(D)
glucose
4
Which of the following solids has a network structure?
คำตอบ
(A)
Diamond
5
Trioxosulphate (lV) acid is not stored for a long period because it
คำตอบ
(C)
is unstable and eaily decomposed
6
Alkanes are used mainly
คำตอบ
(B)
as domestic and industrial fuels
7
Which of the following pairs illustrates isotopy?
คำตอบ
(D)
Hydrogen and deuterium
8
Carbon is often deposited in the exhaust-pipe of cars because of the?
คำตอบ
(C)
incomplete combustion of petrol
9
What does X atand for in the following expression? X = Log(10)(H+)
คำตอบ
(D)
Degree of acidity (pH)
10
Sulphur burns in air to form
คำตอบ
(A)
an acidic oxide
11
In which of the following changes is ∆S negative ?
คำตอบ
(A)
H2O(l) → H2O(s)
12
Chlorine is is used in water treatment as
คำตอบ
(A)
a germicide
13
Which of the following pieces of deposited if a current of 10A was passed through a solution of copper(ll) salt for 965 seconds? (1F = 96500 C)
คำตอบ
(C)
0.05 mole
14
Some precious stones such as ruby and sapphire consist of aluminum oxide coloured by traces of the oxides of
คำตอบ
(C)
transition metals
15
Consider the reaction represented by the following equation CaCI2(aq) + H 2C2O 4(aq) ⇌ CaC 2O4(s) + 2HCI(aq). Which of the following would dissolve the precipitate of CaC 2O4 formed?
คำตอบ
(D)
Adding concentrated hydrochloric acid
16
The following gases decolorize bromine water except
คำตอบ
(A)
C2H6
17
What volume of distilled water should be added to 400cm3 of 2.0 mole dm-3 \(H_{2}SO_{4}\) to obtain 0.20 mole dm-3 of solution>
คำตอบ
(D)
3,600cm-3
18
Which of the following indicates the correct increasing order of oxidizing power of the halogens?
คำตอบ
(B)
l < Br < CI < F
19
Which of the following substances is a peroxide?
คำตอบ
(A)
Na2O2
20
The component of air that removed when air is bubbled into alkaline pyrogallol solution is
คำตอบ
(B)
oxgyen
21
Which of the following will not affect the degree of hardness in a sample of temporarily hard water?
คำตอบ
(D)
Filtration
22
Examples of polymers include the following except
คำตอบ
(E)
glass
23
When the trioxonitrate (IV) salt of an alkali metal Y is heated, the formula of the residue is
คำตอบ
(B)
YNO2
24
Which of the following compounds of tin is a strong reducing agent?
คำตอบ
(D)
SnH4
25
In which of the following pairs are both substances deliquescent?
คำตอบ
(C)
CaCI2 and NaOH
26
Producer gas is a mixture of
คำตอบ
(D)
nitrogen and carbon (ll) oxide
27
An alkene may be converted to an alkane by
คำตอบ
(D)
hydrogenation
28
Which of the following gases are diatomic except
คำตอบ
(B)
helium
29
Which of the following is correct about the electrons in the 1s orbital? They
คำตอบ
(C)
are closest to the nucleus
30
The product of the reaction between ethanol and excess acidified K\(_2\)Cr\(_2\)O\(_7\) is
