Catalytic hydrogenation of oils results in the production of
Одговорити
(E)
margarine
2
Which of the following reaction will not take place under normal conditions?
Одговорити
(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?
Одговорити
(B)
Chromatography
4
The electronic configuration 1s2 22s 22p 63s23p 6 is that of a
Одговорити
(A)
noble gas
5
The heat accompanying the reaction represented by the equation H2O (l) → H 2O(g) is described as the heat of
Одговорити
(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
Одговорити
(D)
forms thin layer of inert oxide in moist air
7
When a solid melts and consequently boils, there is
Одговорити
(A)
a gradual increase in the average kinetic energy of the particles
8
Which of the following compounds will undergo additional reactions?
Одговорити
(A)
Ethyne
9
Which of the following reactions does not occur in the blast furnace during the extraction of iron?
Одговорити
(E)
2Fe2O(s) → 4Fe(l) 3O2(g)
10
A catayst which increases the rate of a chemical reaction does so by
Одговорити
(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)
Одговорити
(B)
3.0 x 1023
12
Which of the following correctly explains entropy?
Одговорити
(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
Одговорити
(B)
\(SO_{2}\)
14
Which of the following salts in aqueous solution will have a pH greater than 7?
Одговорити
(E)
K 2CO3
15
The compound of copper which is used in electroplating dyeing, printing, wood preservation and as a fungicide is
Одговорити
(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)
Одговорити
(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?
Одговорити
(A)
MX2
18
Which of the following pollutants is biodegradable ?
Одговорити
(A)
Sewage
19
In the reaction represented by the equation; 2FeCI3 + SO2 + 2H2O → 2FeCL2 + H2SO4 + 2HCI the oxidation number of sulphur changes from
Одговорити
(B)
+ 4 to + 6
20
Which of the following equations represents the reaction leading to the removal of permanent hardness of water?
Одговорити
(B)
MgSO4 + Na 2CO3 + Na 2SO
21
The following alloys contain copper except
Одговорити
(A)
magnalium
22
How many mole of AgNO\(_3\) are there in 500cm\(^3\) of 0.01M AgNO\(_3\) solution?
Одговорити
(A)
0.005 mole
23
Which of the following statements explains why tetraoxosulphate (IV) acid is reqarded as a strong acid?
Одговорити
(C)
the acid is complately ionized in aqueous solution
24
Which of the following is not correct of glucose and fructose?They
Одговорити
(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?``
Одговорити
(E)
1092k
26
Which of the following explains why trioxonitrate (V) acid is not used for preparing hydrogen from metals?
Одговорити
(B)
it is strongly oxidizing
27
Which of the following is normally used for drying ammonia gas?
Одговорити
(B)
Calcium oxide
28
Nuclear reactions can be used in the following except
Одговорити
(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)
Одговорити
(E)
68 g
30
Which of the following compounds crystallizes without water of crystallization?
