Which of the following sugars is a product of the condensation of monosaccharides?
คำตอบ
(B)
maltose
3
The cleansing effect of soap is low in acidic water because of
คำตอบ
(A)
the formation of unionized fatty acid.
4
The following compounds are condensation polymers except
คำตอบ
(D)
polyethene
5
What amount of electricity is required to deposit one mole of aluminium from a solution of AlCl3?
คำตอบ
(C)
Three Faradays
6
Which of the following compounds would react rapidly with bromine?
คำตอบ
(C)
Hexene
7
Alkanols can be manufactured from alkenes by the initial reaction of alkenes with
คำตอบ
(B)
concentrated tetraoxosulphate(VI) acid
8
Which of the following statements about the standard hydrogen electrode is not correct?
คำตอบ
(D)
The temperature is kept at 20 °C
9
If 60 g of M combines with 24 g of oxygen, what would the empirical formula of the oxide be?
( molar mass of M = 120, O = 16)
คำตอบ
(C)
MO\(_{3}\)
10
The products of the electrolysis of dilute sodium chloride using carbon electrodes are
Anode Cathode
คำตอบ
(B)
oxygen and hydrogen.
11
Determine the quantity of electricity used when a current of 0.20 amperes is passed through an electrolytic cell for 60 minutes.
คำตอบ
(D)
720C
12
Oxochlorate(I) acid is used as a bleaching agent because it is
คำตอบ
(C)
an oxidizing agent
13
The IUPAC name for CH\(_{3}\)CHCH\(_{3}\)CHCLCHCH\(_{3}\)CH\(_{2}\)CH\(_{3}\) is
คำตอบ
(D)
3 - chloro - 2, 4 - dimethylhexane
14
A colourless gas with a pungent smell is evolved when dilute hydrochloric acid is added to a sample of a salt. The gas evolved could turn
คำตอบ
(B)
acidified KMnO\(_{4}\) solution colourless
15
If 5.0 g of marble reacts with 25.0 cm3 hydrochloric acid, which of the following combinations has the fastest reaction rate?
คำตอบ
(C)
Powdered marble and 2.5 mol dm\(^{-3}\) HCl\(_{(aq)}\)
16
Increasing the temperature generally
คำตอบ
(B)
increases the solubility of a solid in a liquid but decreases the solubility of a gas in a liquid.
17
A white precipitate was formed when BaCl\(_{2(aq)}\) was added to an aqueous solution
of a salt X. The precipitate dissolved in dilute HCl with rapid effervescence. Salt X is likely to contain
คำตอบ
(B)
SO\(_{3}\) \(^{2-}\) ions
18
Before a reaction could take place, there should be
คำตอบ
(C)
breakage of bonds of reactants
19
Consider the following reaction equation:
CaO + SiO\(_{2}\) ------> CaSiO\(_{3}\)
Silicon(IV) oxide is acting as
คำตอบ
(C)
an acidic oxide
20
Which of the following acids would form normal salt only?
คำตอบ
(B)
Trioxonitrate(V) acid
21
What is the partial pressure of oxygen at s.t.p. in a gaseous mixture containing 100 cm3 of oxygen and 900 cm3 of nitrogen gas?
คำตอบ
(B)
0.1 atm
22
Graphite is used as a dry lubricant due to the presence of
คำตอบ
(D)
layered structures
23
Which of the following gases is alkaline?
คำตอบ
(C)
NH\(_{3}\)
24
Which of the following statements about an equilibrium system is correct?
คำตอบ
(A)
Forward and backward reactions occur
at the same rate
25
Consider the following reaction equation
N\(_{2}\)(g) + 3H\(_{2(g)}\) ⇌ 2NH3(g) ∆H = -92kJ
Increasing the temperature of the reaction would
คำตอบ
(D)
decrease the yield of ammonia
26
When air in a syringe is compressed such that there is no change in temperature, the
คำตอบ
(B)
pressure increases
27
Which of the following statements about liquids is/are true?
I. Liquids maintain their volume at constant temperature.
II. Liquids have fixed shape
III. Liquids do not diffuse
IV. Change in pressure affects volume of liquids
คำตอบ
(A)
I only
28
A hydrogen chloride gas reacted with oxygen gas to yield water and chlorine gas. The mole ratio of the hydrogen chloride gas to water is
คำตอบ
(B)
2:1
29
What number of moles of oxygen would exert a pressure of 10 atm at 320 K in an 8.2 dm\(^{3}\) cylinder?
[R=0.082 atm dm\(^{-3}\) mol\(^{-1}\) K\(^{-1}\)]
คำตอบ
(C)
3.13
30
If 50 cm\(^{3}\) of a saturated solution of KNO\(_{3}\) at 40 °C contained 5.05 g of the salt, its solubility at the same temperature would be
[KNO\(_{3}\) = 101]
คำตอบ
(A)
1.0 mol dm\(^{-3}\)
31
Which of the following elements would displace copper from a solution of copper ions?
คำตอบ
(C)
lead
32
What is the percentage composition of carbon
in Ca(HCO3)\(_{2}\) ?
[ Ca = 40.0, 0= 16.0, C = 12.0, H= 1.0]
คำตอบ
(B)
14.8%
33
Which of the following bond types is intermolecular?
คำตอบ
(B)
Hydrogen bond
34
The maximum number of covalent bonds formed by nitrogen is
คำตอบ
(D)
4
35
The IUPAC name of the compound CH3CH(CH3)CHCH2 is
คำตอบ
(C)
3 - methyl but - 1 - ene
36
Ionization energy increases across the period in the periodic table because
คำตอบ
(B)
effective nuclear charge increases
37
Which of the following properties indicate that an element is a metal. It
I. reacts with oxygen to form an acidic oxide
II. forms ionic chlorides
III. has variable oxidation states
IV. displaces hydrogen from dilute HCl
คำตอบ
(C)
II and IV only
38
The electron configuration of carbon atom in its excited state is
