Catalytic hydrogenation of oils results in the production of
إجابة
(E)
margarine
2
Which of the following reaction will not take place under normal conditions?
إجابة
(C)
Cu (s) + 2HCI (aq) → CuCI 2(aq) + H2(g)
3
A sample of orange juice is suspected to have been contaminated with a yellow dye. Which of the following methods can be used to detect the dye?
إجابة
(B)
Chromatography
4
The electronic configuration 1s2 22s 22p 63s23p 6 is that of a
إجابة
(A)
noble gas
5
The heat accompanying the reaction represented by the equation H2O (l) → H 2O(g) is described as the heat of
إجابة
(C)
vaporization
6
Aluminum is above iron in the electrochemical series, yet iron corrodes easily on exposure to air while aluminium does not. This is because aluminium
إجابة
(D)
forms thin layer of inert oxide in moist air
7
When a solid melts and consequently boils, there is
إجابة
(A)
a gradual increase in the average kinetic energy of the particles
8
Which of the following compounds will undergo additional reactions?
إجابة
(A)
Ethyne
9
Which of the following reactions does not occur in the blast furnace during the extraction of iron?
إجابة
(E)
2Fe2O(s) → 4Fe(l) 3O2(g)
10
A catayst which increases the rate of a chemical reaction does so by
إجابة
(E)
decreasing the activation energy of the reaction
11
How many molecules are there in 14g of nitrogen gas at s.t.p? (n = 14, Avogadro Number = 6. 0 x \(10^{23 }\)mol-1)
إجابة
(B)
3.0 x 1023
12
Which of the following correctly explains entropy?
إجابة
(A)
the natural tendency for a system to achieve a greater disorder
13
The gas that is liberated when iron is heated with concentrated tetraoxosulphate (VI)acid is
إجابة
(B)
\(SO_{2}\)
14
Which of the following salts in aqueous solution will have a pH greater than 7?
إجابة
(E)
K 2CO3
15
The compound of copper which is used in electroplating dyeing, printing, wood preservation and as a fungicide is
إجابة
(C)
copper (ll) tetraoxosulphate (VI) pentahydrate
16
What is the molecular formula of a compound whose empirical formula is CH2O and molar mass is 180? (H = 1, C = 12, O = 16)
إجابة
(D)
C 6H 12O6
17
MO and X 2O represent the formula of oxides of elements M and X respectively . If M and X should combine to form a separate compound, what would be the formula of the compound?
إجابة
(A)
MX2
18
Which of the following pollutants is biodegradable ?
إجابة
(A)
Sewage
19
In the reaction represented by the equation; 2FeCI3 + SO2 + 2H2O → 2FeCL2 + H2SO4 + 2HCI the oxidation number of sulphur changes from
إجابة
(B)
+ 4 to + 6
20
Which of the following equations represents the reaction leading to the removal of permanent hardness of water?
إجابة
(B)
MgSO4 + Na 2CO3 + Na 2SO
21
The following alloys contain copper except
إجابة
(A)
magnalium
22
How many mole of AgNO\(_3\) are there in 500cm\(^3\) of 0.01M AgNO\(_3\) solution?
إجابة
(A)
0.005 mole
23
Which of the following statements explains why tetraoxosulphate (IV) acid is reqarded as a strong acid?
إجابة
(C)
the acid is complately ionized in aqueous solution
24
Which of the following is not correct of glucose and fructose?They
إجابة
(C)
can be obtained by the hydrolysis of starch
25
To what temperature must a gas be raised from 273K in order to double both its volume and pressure?``
إجابة
(E)
1092k
26
Which of the following explains why trioxonitrate (V) acid is not used for preparing hydrogen from metals?
إجابة
(B)
it is strongly oxidizing
27
Which of the following is normally used for drying ammonia gas?
إجابة
(B)
Calcium oxide
28
Nuclear reactions can be used in the following except
إجابة
(E)
purifying water
29
The decomposition of hydrogen peroxide is represented by the equation: 2H2O(l) + O2(g) what mass of hydrogen peroxide would be required to produce 22.4dm3 of oxygen at s.t.p? (H = 1, O = 16, molar volume of a gas at s.t.p. = 22.4dm3)
إجابة
(E)
68 g
30
Which of the following compounds crystallizes without water of crystallization?
