Which of the following species determines the chemical properties of an atom?
Trả lời
(A)
Electron
2
The following glasswares are used to measure the volume of liquids EXCEPT
Trả lời
(C)
test tube
3
Pauli exclusion principle is related to
Trả lời
(D)
quantum numbers of electrons
4
The species with no electron in the 3d-orbital is
Trả lời
(B)
\(Sc^{3+}\)
5
The seperation of Nitrogen from oxygen using fractional distillation of air is possible because
Trả lời
(C)
of the difference in their boiling points
6
The purity of a solid sample can best be determined by its
Trả lời
(B)
melting point
7
The mass of one mole of \((NH_{4})_{2}CO_{3}\) is [O=16.0, N=14.0, C=12.0, H=1.0]
Trả lời
(D)
96.0g
8
Atomic orbital is
Trả lời
(B)
a region around the nucleus where electrons are most likely to be found
9
The property of elements which increases down a group of the periodic table is
Trả lời
(C)
ionic radius
10
The reason for the decrease in the atomic size of elements across a period is that
Trả lời
(A)
nuclear charge increases while the outermost electrons are drawn closer to the nucleus
11
The oxidation number of nitrogen in \(Pb(NO_{3})_{2}\) is
Trả lời
(D)
+5
12
Which of the following arrangements indicates the correct decreasing order of ionization energy of period 3 elements?
Trả lời
(B)
Cl, P, Al, Na
13
Which of the following metals has the strongest metallic bond?
Trả lời
(A)
\(_{13}Al\)
14
Which of the following substances does not have van der Waals' forces?
Trả lời
(A)
Copper
15
The oxidation number of X in \(XO_{4}^{3-}\) is
Trả lời
(D)
+5
16
The ionization energy is affected by the following factors except
Trả lời
(C)
ability to attract shared electron(s)
17
Which of the following statements is correct?
Trả lời
(D)
Ionic compounds in solution would conduct electricity
18
The bond angle in tetrahedral molecules such as tetrachloromethane is
Trả lời
(B)
109.5°
19
The properties of a good primary standard include the following except
Trả lời
(B)
low molecular mass
20
The use of diamond in abrasives is due to its
Trả lời
(B)
hardness
21
Which of the following statements about endothermic reaction is correct?
Trả lời
(D)
Heat energy is absorbed
22
A 0.1\(moldm^{-3}\) solution of sodium hydroxide was diluted with distilled water to 0.001\(moldm^{-3}\). What is the dilution factor?
Trả lời
(B)
100.00
23
Graphite and Diamond are similar in that they
Trả lời
(C)
form carbon(IV) oxide on combustion
24
In a saturated solution at a given temperature, the undissolved solutes are in equilibrium with
Trả lời
(B)
dissolved solute particles
25
The number of atoms present in 2.5moles of a triatomic gas is equivalent to [1mole = \(6.02\times 10^{23}\)]
Trả lời
(C)
\(1.5\times 10^{24}\)
26
When Magnesium reacts with oxygen, heat is
Trả lời
(C)
evolved and the reaction is exothermic
27
Which of the following gases is not acidic?
Trả lời
(D)
CO
28
A hydrocarbon contained 14.3% hydrogen. The empirical formula for the hydrocarbon is [H= 1.0, C= 12.0]
Trả lời
(B)
\(CH_{2}\)
29
Which of the following statements is NOT a chemical property of an acid?
Trả lời
(A)
Evolution of ammonia when heated with ammonium salts
30
Halogens generally react with metals to form
Trả lời
(D)
salts
31
Potassium Chloride solid does not conduct electricity because
Trả lời
(B)
strong cohesive forces make its ions immobile
32
When water was added to a white anhydrous substance X, the colour changed to blue. X is
Trả lời
(A)
\(CuSO_{4}\)
33
Solubility curve can be used in the determination of the
Trả lời
(C)
amount of solid drugs in a given solution
34
If 0.2g of a salt is required to saturate 200\(cm^{3}\) of water at room temperature, what is the solubility of the salt?
Trả lời
(B)
1.0\(gdm^{-3}\)
35
The property of a chemical reaction that is affected by the presence of a catalyst is
Trả lời
(A)
activation energy
36
Soluble salts can be prepared by the following methods except
Trả lời
(C)
double decomposition
37
Chemical reactions occurs when the colliding reactants have energy that is
Trả lời
(B)
greater than the activation energy
38
The common feature of reactions at the anode is that
Trả lời
(C)
oxidation is involved
39
Consider the following reaction equation: \(2NO_{(g)} + O_{{2}{(g)}} \to 2NO_{{2}{(g)}}\). What is the change in the oxidation number of nitrogen?
Trả lời
(C)
+2 to +4
40
Which of the following factors characterize members of the same homologous series?
Trả lời
(D)
Successive members undergo changes in molecular formula by \(CH_{2}\)
41
Calculate the mass of copper deposited if a current of 0.45A flows through \(CuSO_{4}\) solution for 1hour 15mins. [Cu=64.0, S= 32.0, O =16.0, 1F= 96500C]
Trả lời
(B)
0.67g
42
Classification of alkanols is based on the
Trả lời
(D)
number of alkyl groups bonded to the carbon having the hydroxyl group
43
The name of the compound \(C_{4}H_{9}COOC_{3}H_{7}\) is
Trả lời
(A)
propyl pentanoate
44
Which of the following pairs of gases are pollutants from car exhaust?
Trả lời
(C)
Carbon(II) oxide and Sulphur(IV) oxide
45
Fats and oils can be obtained from any of the following sources except
