In which of the following is the oxidation number of nitrogen zero?
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(E)
N2
3
The separation of a mixture of calcium trioxocarbonate (lV) and sodium trioxocarbonate (IV) is most easily carried out by using the differences in their
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(D)
solubility
4
When air is passed through a heated tube containing finely divided copper, the component that is absorbed in the process is
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(C)
oxygen
5
What is the amount (in mole) of sodium trioxocarbonate (IV) in 5.3 g of the compound? (Na2CO3 = 106)
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(A)
0.05
6
Which of the processes represented by the following equations has the greatest positive entropy change?
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(A)
C6H3(l) → C6H 6(g)
7
Which of the following elements can from more than one acidic oxide?
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(B)
Sulphur
8
CH2 = CH2 + H2SO4 → CH3 - CH2 -OSO3H. The reaction illustrated by the equation above is an example of
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(D)
addition
9
Brass is an alloy of copper and
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(C)
zinc
10
Which of the following formula is that of a dicarboxylic acid?
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(D)
CH2(COOH)2
11
The products of the electrolysis of dilute sodium chlorid solution with platinum electrodes are
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(A)
hydrogen and oxygen
12
Which of the following modes of motion is exhibited by the particles of a solid?
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(D)
Vibrational motion only
13
Which of the following statements is not correct? Group 7 elements
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(D)
have relatively low ionization potentials
14
In which of the following are the substances arranged in their correct order of increasing melting point?
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(C)
Sulphur, sodium chloride, diamond
15
A compound which liberates carbon (IV) oxide from a hydrogentrioxocarbonate (lV) could have the molecular formula
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(C)
HCOOH
16
CH4(g) + 2O2(g) → 2H2O(l) + CO2(g) ∆H = 890KJ mo-1 ∆H in the reaction represented by the equation above is the enthalpy of
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(B)
combustion
17
Consider the reaction represented by the equation below: H2(g) + 12(s) ⇌ 2HI(g) ∆H negative. Which of the following takes place when the temperature of the reaction vessel is decreased?
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(E)
the yield of hydrogen iodide increases
18
2NaNO3 → 2NaNO2 + O2. From the equation above, what is the volume of oxygen produced at s.t.p. when 8.5g of 2NaNO3 is heated until no further gas is evolved? (2NaNO3 = 85, molar volume of gases at s.t.p. = 22.4dm3)
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(A)
1.12dm3
19
Esterification of propane 1,2,3-triol and unsaturated higher carboxylic acids will produce
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(C)
methly-propanoate
20
The ratio of reactants to products is 1: 3: 2 in the reaction represented by the equation below: N2,/SUB> (g) → 2NH3(g) which of the following law is demonstrated by this?
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(C)
Gay Lussac's law
21
In the redox reaction represented by the following equation: Cu2+aq + Zn(s) → Cu(s) + Zn2+
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(B)
copper (ll) ions are reduced to copper atoms
22
When starch undergoes complete enzyme-catalyzed hydrolysis, the resulting product is
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(A)
glucose
23
Which of the reactions represented by the following equations will take place at room temperature?
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(D)
2Na + 2H2O → 2NaOH + H2
24
Which of the following is not a direct petroleum product?
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(D)
Vaseline
25
How many principal electronic shells has an atom whose electronic configuration is shown below? 1s22s22p63s1
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(C)
3
26
Which of the following properties is not characteristic of electrovalent compounds?
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(C)
high vapour pressures
27
Compounds that have the same molecular formula but different structures are said to be
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(D)
isomeric
28
In which of the following crystals are the particles held by van der Waal's forces only?
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(D)
Iodine
29
A current of 4.0 amperes was passed through copper (ll) tetraoxosulphate (IV) solution for one hour using copper electrodes. What was the mass of copper deposited? (Cu = 64, 1F = 96500 C)
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(B)
4.8g
30
When a crystal was added to its solution, it did not dissolve and the solution remained unchanged, showing that the solution was
