Which of the following statements about rare gases are correct?
إجابة
(A)
Their outermost shells are fully filled
3
Which of the following properties is characteristic of the halogens?
إجابة
(A)
Ability to accept electrons readily
4
In which of the following atoms is the ionic radius larger than the atomic radius? [11 Na, 12Mg,13AI,17CI]
إجابة
(B)
Chlorine
5
A transition metal would be expected to
إجابة
(A)
from oxides with different formulae
6
Which of the following properties of atoms generally increases down a group in the periodic table?
إجابة
(C)
Ionic radius
7
Which of the following statements about sodium is not true?
إجابة
(B)
Na is smaller in size than Na+
8
If the difference between the electronegativities of two elements is large, the type of bond that can be formed between them is
إجابة
(C)
ionic
9
Which of the following compounds has hydrogen bonds between its molecules?
إجابة
(A)
HF
10
Which of the following species does not contain a co-ordinate bond?
إجابة
(A)
AI2CI6
11
14.8 g of a salt (z)dissolved in 250 cm3 of distilled water gives a concentration of 0.80 mol dm-3. Calculate the molar mass of the salt (z).
إجابة
(D)
74.0 g mol-1
12
How many atoms are there in one mole of hydrogen gas? [Avogadro's constant = 6.02 x 1023mol-1]
إجابة
(C)
1.2 x10 24
13
What is the IUPAC name of the compound represented by the molecular formula NaCIO4?
إجابة
(D)
Sodium tetraoxochlorate(VII)
14
When air is successively passed through sodium hydroxide solution, alkaline pyrogallol and then concentrated tetraoxosulphate (VI) acid, its remaining components are
إجابة
(D)
nitrogen and noble gases
15
Which of the following gases is light than air?
إجابة
(D)
NH3
16
Which of the following statements is true of the molecules of a gas under ideal conditions? The molecules
إجابة
(A)
move at random
17
In which of the following compound (s) will heat be absorbed on adding water?
l. KNO\(_3\) II. Concentrated H\(_2\)SO\(_4\) III. NH\(_4\)CI
إجابة
(C)
l and lll only
18
Consider the reaction represented by the equation: Ca(OH)2(aq) + CO 2(g) → CaCO3(s) + H 2O(l)
in the reaction above, CO 2 acts as
إجابة
(A)
an acidic oxide
19
Which of the following compounds is a basic salt?
إجابة
(D)
Zn(OH)CI
20
What process is illustrated below? S(s) ⇌H2O⇌ S (aq)
إجابة
(C)
Formation of saturated solution of a solid
21
A solution of a salt X reacts with AgNO3 solution to give white precipitate which dissolves in excess aqueous ammonia. X contains
إجابة
(A)
CI-
22
Consider the reaction represented by the following equation: N2(g) + 3H2(g) ⇌ 2NH3(g); ∆H = - 92kJmol1. Finely divided iron is used as catalyst in the reaction in order to
إجابة
(C)
shorten the time for attainment of equilibrium
23
Which of these cell notations is the correct representation of a Daniell cell?
إجابة
(A)
Zn(s) / Zn2+(aq) // Cu2+(aq)/Cu(s)
24
What is the oxidation number of chromium in K2CrO4?
إجابة
(D)
+6
25
What product is formed at the cathode during the electrolysis of concentrated sodium chloride solution using carbon electrodes?
إجابة
(B)
Hydrogen
26
Which of the following substances is suitable solvent for perfumes?
إجابة
(B)
Ethanol
27
The complete hydrogenation of C 6
H 6 in the presence of nicked catalyst at 200oC gives
إجابة
(C)
C 6H 12
28
Which of the following pairs of substances can be distinguished by use of NaHCO3 solution?
إجابة
(B)
CH 3CH2OH and CH3COOH
29
Alkenes undergo the following reactions except
إجابة
(D)
substitution
30
Hydrocarbons which react with ammoniacal copper (l) chloride solution conform to the general molecular formula
إجابة
(D)
CnH2n-2
31
Consider the reaction below: Vegetable oil \(\frac{H2;NI catalyst}{High temperature}\) product. The reaction is applied in the manufacture of?
إجابة
(B)
margarine
32
Which of the following compounds reacts readily with sodium to liberate hydrogen?
إجابة
(B)
CH3COOH
33
Glucose reduces Fehling's solution on warming to
إجابة
(A)
copper (l) oxide
34
from the following ores is iron extracted? I. Haematite ll. Bauxite III. Magnetite IV. Cassiterite
إجابة
(B)
l and lll only
35
Which of the following methods can be used to separate a mixture of two miscible liquids with different boiling points?
