The number of orbitals in a p-sub level of an atom is
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(B)
3
2
Which of the following electron configurations represents that of an atom in its ground state?
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(D)
1s22s22p63s0
3
Which of the following ions has an electron configuration different from the other?
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(A)
17CI-
4
The atomic radii of metals are usually
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(A)
greater than their ionic radii
5
Two elements, X and Y are in the same group on the periodic table because they both have the same
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(B)
number of valence electrons
6
The d-block elements are paramagnetic because they
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(B)
contain unpaired electrons in the partially filled 3d-orbital
7
Which of the following statements about a radioactive substance is/are correct? l. lt emits radiation continuously and spontaneously. ll. The emitted radiations are affected by temperature and pressure III. The radiation can penetrate opaque matter
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(C)
l and lll only
8
Which of the following elements is a metalloid?
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(C)
Silicon
9
Which of the following halogens is liquid at room temperature?
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(D)
Bromine
10
The shape of a graphite crystal is
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(C)
hexagonal
11
The complex compound formed by the combination of two elements with a large electronegativity difference is likely to be
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(D)
ionic
12
The complex compound formed when aluminum dissolves in aqueous sodium hydroxide is
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(B)
NaAl(OH)4
13
The vapour pressure of a liquid depends on l. temperature. ll. rate of condensation. III. cohesive forces holding the particles together
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(C)
l and lll only
14
MgO does not readily dissolve in water because
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(D)
its lattice energy is higher than its hydration energy
15
Consider the following reaction equation: CaCO\(_{3(s)}\) + 2HCI\(_{(aq)}\) → CaCl\(_{2(aq)}\) + H\(_2\)O\(_{(l)}\) + CO\(_{2(g)}\). What mass of CaCI\(_2\) would be obtained when 25.0g of CaCO\(_{3(s)}\) is reacted with excess HCI\(_{(aq)}\)? [CaCO\(_3 = 100; CaCI\(_2\) = 111]
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(D)
27.8 g
16
The number of sulphur atoms in 3.20g of SO\(_{2(g)}\) is [O = 16.0;S = 32.0; Avogadro constant = 6.02 x 10\(^{23}\)]
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(A)
3.01 x 1022
17
Consider the reaction represented by the following equation: xCH\(_3\)OH + yO\(_2\) → 2CO\(_2\) + zH\(_2\)O. The values of x,y and z respectively, are
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(A)
2,3 and 4
18
The formula of mercury (l) dioxonitrate (III) is
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(C)
Hg2(NO2)2
19
A sample of a gas may be identified as chlorine if it turns
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(D)
starch iodide paper blue-black
20
A metal M forms two types of chlorine, MCl\(_2\) and MCl\(_3\) which of the following laws best explains the relationship between the chlorides? Law of
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(C)
multiple proportion
21
Which of the following metals would readily displace hydrogen from steam?
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(C)
Magnesium
22
The volume occupied by 0.4 g of hydrogen gas at s.t.p. is [H = 1. 00; Molar volume at s.t.p. = 22.4 dm3]
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(B)
4.48dm3
23
When a substance changes directly from the solid state to the gaseous state without forming a liquid, the substance is said to
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(C)
sublime
24
At ordinary temperature H\(_2\)O is a liquid while H\(_2\)S is a gas. This is because H\(_2\)O has
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(B)
strong hydrogen bonds holding its molecules together
25
The postulate that molecules are in constant random motion best explains why liquids
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(A)
can undergo solidification
26
Which of the following gases has the lowest rate of diffusion under the same condition? [H = 1.00; He = 4. 00; O = 16.0; CI = 35.5]
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(A)
CI2
27
The energy evolved when magnesium burns in air is in the form of
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(C)
light and heat
28
A substance L reacts with NH\(_4\)NO\(_{3(aq)}\) to generate ammonia gas. L is likely to be
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(B)
NaOH
29
On heating, the following trioxocarbonate (IV) salts decompose to give solid residue except
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(A)
ammonium trioxocarbonate (IV)
30
Which of the following pH values indicates that a solution is a strong base?
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(D)
13
31
The hydrolysis of NH\(_4\)CI gives
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(A)
an acidic solution
32
A spot of oil paint on a shirt can best be removed using?
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(C)
kerosine
33
Consider the reaction represented by the following equation: CuO\(_{(s)}\) + H\(_2\)SO\(_{4(aq)}\) → CuSO\(_{4(aq)}\) + H\(_2\)O\(_{(l)}\). Which of the following factors will not affect the rate of the reaction?
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(D)
Pressure of reaction system
34
Which of the following devices function on redox reaction? l. Dry cell ll. Car battery III. Electric generator
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(C)
l and ll only
35
The oxidation number of Fe in [Fe(CN)\(_6\)]\(^{3-}\) is
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(A)
+3
36
Consider the following reaction equation: C\(_{16}\)H\(_{34}\) → C\(_5\)H\(_{12}\) + C\(_{11}\)H\(_{22}\). The process represented by the equation is
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(A)
cracking
37
Which of the following substances would not produce ethanol when fermented?
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(D)
Vinegar
38
An alkanol can be prepared by the reaction of an alkene with
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(A)
concentrated tetraoxosulphate (VI) acid
39
A tertiary alkanol has a molecular formula C\(_4\)H\(_{10}\)O. What is the structural formula of the compound?
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(C)
(CH3)3COH
40
Which of the following industrial processes depends on the action of enzymes?
