The formation of a bond between hydrogen and a highly electronegative atom results in
إجابة
(A)
polarity
7
Which of the elements in the table below would react more readily with chlorine?
Element
Ionization energy (KJ \(mol^{-1} \times 10^{-3}\))
W
12.0
X
21.0
Y
106.0
Z
200.0
إجابة
(C)
W and X only
8
Which of the following properties does not give evidence of the kinetic theory of matter?
إجابة
(C)
Polymerization
9
Dilute trioxonitrate (V) acid does not produce hydrogen when it reacts with metals because
إجابة
(D)
it is a strong oxidizing agent.
10
Which of the following statements is correct?
إجابة
(D)
An alkane with 49 carbon atoms contains 100 hydrogen atoms
11
A mixture containing two salts of different solubility can be separated by
إجابة
(B)
crystallization.
12
Species that occur in a reaction pathway but not in the overall reaction are known as
إجابة
(D)
Intermediates
13
How many moles are there in 3.0 g of \(O_2\)? [O = 16.0]
إجابة
(B)
0.0930 moles.
14
Which of the following equimolar solutions has the highest conductivity?
إجابة
(A)
\(H_2SO{_4(aq)}\)
15
The pair of compounds that belongs to the same homologous series is
إجابة
(A)
\(C_2H_6\) and \(C_4H_{10}\)
16
Which of the following equations does not illustrate correctly one of the reactions of chlorine?
إجابة
(B)
\(Cl_2 + 2NaF → 2NaCl + F_2\)
17
The salt solution formed firm a reaction between ethanoic acid and sodium hydroxide solution would be
إجابة
(C)
basic
18
The separation technique that is suitable for separating iodine from tetrachloromethane is
إجابة
(A)
solvent extraction
19
Consider the following reaction equation:
\(2SO_3(g) → 2SO_2(g) + O_2\)(g)
∆H = +198 kJ/mol
Which of the following statements about the reaction is correct?
إجابة
(D)
198 kJ of energy is absorbed
20
Arrange the following compounds in decreasing order of their boiling points: \(NH_3\), HF, \(SiH_4\), \(CH_4\)
إجابة
(A)
HF,\(NH_3\), \(SiH_4\), \(CH_4\)
21
Copper (II) ions are able to participate in co-ordinate covalent bonding because they
إجابة
(C)
have vacant d-orbital
22
What takes place at the cathode during electrolysis?
إجابة
(D)
Cations are discharged.
23
Carbon is deposited in the exhaust pipes of cars because of
إجابة
(B)
incomplete combustion of petrol
24
Which of the following laws or theory cannot be explained by the application of the kinetic theory of gases?
إجابة
(A)
Dalton's atomic theory
25
How many unpaired electrons are present in \(_{26}Fe^{3+}\)?
إجابة
(D)
5
26
A consequence of global warming is
إجابة
(C)
flooding
27
Going down group II in the periodic table normally
إجابة
(B)
melting point increases
28
The primary component of natural gas
إجابة
(B)
methane
29
The gas that is less dense than air is
إجابة
(A)
nitrogen
30
The periodic property that is used to determine whether a covalent molecule is polar or not is
إجابة
(D)
electronegativity
31
If \(100^3\) of a saturated solution of sodium tetraoxosulphate (VI) at 30° C contains 10.5 g of the salt, what would be its solubility at this temperature? [(\(Na_2SO_4\) = 142]
إجابة
(B)
0.74 mol dm-3
32
A compound that could be dried by using conc. tetraoxosulphate (VI) acid and not by calcium oxide is likely to be
إجابة
(D)
an acid anhydride
33
Which of the statements about gases is not correct?
إجابة
(D)
Gases are highly soluble in water at high temperatures
34
Determine the volume of 0.100 mol of HCl in \(0.250 mol dm^3\) of solution.
إجابة
(D)
\(400cm^3\)
35
Positive ions in a sea of electrons are found in
إجابة
(B)
metallic bonds
36
An element X has two isotopes, \(^{65}X_{30}\) and \(^{66}X_{30}\) with relative abundance of 60 % and 40% respectively. The relative atomic mass of X is
إجابة
(D)
65.40
37
Which of the following statements about the collision theory is correct?
إجابة
(C)
The rate of reaction is proportional to the number of effective collisions
38
Which of the following elements has its valence electrons in the s-orbital?
إجابة
(C)
Sodium
39
Petrochemistry is an example of
إجابة
(A)
applied chemistry
40
The molecule that has a non-polar covalent bond is
إجابة
(C)
\(Cl_2\)
41
The reduction half equation of the following reaction is:
\(Zn_{(s)} + CuSO_{4(aq)} → ZnSO_{4(aq)} + Cu_{(s)}\)
إجابة
(C)
\(Cu^{2+}_{(aq)} + 2e^- → Cu_{(s)}\)
42
Why are \(H_2SO_4\) and \(CaCl_2\), not suitable for drying ammonia gas? They
إجابة
(D)
react with the gas
43
Isoelectronic species have the same number of
إجابة
(B)
electrons
44
Which of the following gases has the lowest rate of diffusion?
[H=1.0, C=12.0, N = 14.0, O= 16.0]
إجابة
(D)
Oxygen
45
An example of a crystalline substance that does not possess water of crystallization is
