Which of the following species determines the chemical properties of an atom?
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(A)
Electron
2
The following glasswares are used to measure the volume of liquids EXCEPT
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(C)
test tube
3
Pauli exclusion principle is related to
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(D)
quantum numbers of electrons
4
The species with no electron in the 3d-orbital is
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(B)
\(Sc^{3+}\)
5
The seperation of Nitrogen from oxygen using fractional distillation of air is possible because
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(C)
of the difference in their boiling points
6
The purity of a solid sample can best be determined by its
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(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]
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(D)
96.0g
8
Atomic orbital is
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(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
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(C)
ionic radius
10
The reason for the decrease in the atomic size of elements across a period is that
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(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
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(D)
+5
12
Which of the following arrangements indicates the correct decreasing order of ionization energy of period 3 elements?
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(B)
Cl, P, Al, Na
13
Which of the following metals has the strongest metallic bond?
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(A)
\(_{13}Al\)
14
Which of the following substances does not have van der Waals' forces?
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(A)
Copper
15
The oxidation number of X in \(XO_{4}^{3-}\) is
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(D)
+5
16
The ionization energy is affected by the following factors except
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(C)
ability to attract shared electron(s)
17
Which of the following statements is correct?
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(D)
Ionic compounds in solution would conduct electricity
18
The bond angle in tetrahedral molecules such as tetrachloromethane is
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(B)
109.5°
19
The properties of a good primary standard include the following except
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(B)
low molecular mass
20
The use of diamond in abrasives is due to its
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(B)
hardness
21
Which of the following statements about endothermic reaction is correct?
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(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?
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(B)
100.00
23
Graphite and Diamond are similar in that they
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(C)
form carbon(IV) oxide on combustion
24
In a saturated solution at a given temperature, the undissolved solutes are in equilibrium with
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(B)
dissolved solute particles
25
The number of atoms present in 2.5moles of a triatomic gas is equivalent to [1mole = \(6.02\times 10^{23}\)]
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(C)
\(1.5\times 10^{24}\)
26
When Magnesium reacts with oxygen, heat is
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(C)
evolved and the reaction is exothermic
27
Which of the following gases is not acidic?
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(D)
CO
28
A hydrocarbon contained 14.3% hydrogen. The empirical formula for the hydrocarbon is [H= 1.0, C= 12.0]
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(B)
\(CH_{2}\)
29
Which of the following statements is NOT a chemical property of an acid?
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(A)
Evolution of ammonia when heated with ammonium salts
30
Halogens generally react with metals to form
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(D)
salts
31
Potassium Chloride solid does not conduct electricity because
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(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
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(A)
\(CuSO_{4}\)
33
Solubility curve can be used in the determination of the
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(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?
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(B)
1.0\(gdm^{-3}\)
35
The property of a chemical reaction that is affected by the presence of a catalyst is
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(A)
activation energy
36
Soluble salts can be prepared by the following methods except
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(C)
double decomposition
37
Chemical reactions occurs when the colliding reactants have energy that is
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(B)
greater than the activation energy
38
The common feature of reactions at the anode is that
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(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?
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(C)
+2 to +4
40
Which of the following factors characterize members of the same homologous series?
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(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]
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(B)
0.67g
42
Classification of alkanols is based on the
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(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
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(A)
propyl pentanoate
44
Which of the following pairs of gases are pollutants from car exhaust?
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(C)
Carbon(II) oxide and Sulphur(IV) oxide
45
Fats and oils can be obtained from any of the following sources except
