Which of the following substances is an example of a fine chemical?
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(C)
Ethylene
2
The IUPAC name of the compound represented by the structure below is ?
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(A)
2- chloro but-I ,3-diene.
3
Which or the following substances is a polypeptide?
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(C)
Protein
4
Which or the following products could be formed during incomplete combustion of a hydrocarbon.
i.Carbon ii. Hydrogen III. Carbon (Il) oxide
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(C)
I and III only
5
What quantity of electrons is lost when one mole of iron (II) ions is oxidized to iron (III) ?
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(B)
3 moles
6
What is the mass of silver deposited when 24,125 C of electricity is passed through a solution or silver salt.
[Ag = 108, IF = 96,500 C ]
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(D)
27g
7
Equal masses of calcium trioxocarbonate(iv) were added to dilute hydrochloric acid at the temperature specified. Under which of the following conditions would the reaction be slowest?
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(A)
Calcium trioxocarbonate ( iv ) chips a 20°C
8
The high solubility of ethanol in water is due to?
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(D)
hydrogen bonding
9
Which of the following pairs of properties of alkali metals decreases down the group?
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(D)
First ionization energy and melting point
10
The most suitable process of obtaining water from an aqueous solution of sugar i
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(B)
Distillation
11
Group VIl elements in their combined states are called?
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(C)
Halide
12
When an ionic bond is broken, bonding electrons are
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(B)
gained by the most electropositive atom
13
The oxidation state of chlorine in NaClO\(_3\) is?
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(C)
+5
14
A balanced chemical equation is based on the law of?
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(D)
Conservation of mass
15
Which of the following pairs of elements has the greatest difference in electronegativity?
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(A)
Na and F
16
A factor that is considered most important when siting a chemical industry is?
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(B)
nearness to raw materials
17
The boiling point of pentane is higher than that of propane because?
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(B)
Pentane has more covalent bonds to break
18
Which of the following solids would not decompose on heating?
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(C)
Potassium trioxocarbonate (IV)
19
The following molecules have double covalent bonds between two atoms except?
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(D)
water
20
The type of isomerism exhibited by cis and trans isomers is?
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(B)
geometrical
21
Which of the following compounds has the lowest boiling point?
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(A)
C\(_4\)H\(_10\)
22
An alkanol containing 60% carbon by mass would have a molecular formula [H=1.0. C-12.0, O= 16.0]
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(C)
C\(_3\)H\(_7\)OH
23
Which of the following compounds would release hydrogen when reacted with sodium metal?
I. CH\(_3\)COOH
II. CH\(_3\)CH\(_2\)OH
III. CH\(_3\)COOCH\(_3\)
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(B)
I and II only
24
Which of the following substances is not a reducing agent?
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(C)
O\(_2\)
25
Which of the following statements is correet for a reaction at equilibrium?
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(C)
The rates of the forward and backward reactions are equal
26
Which of the following reactions are always exothermic? 1. Neutralization Il. Decomposition III. Combustion
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(B)
I and III only
27
Which of the following standard conditions is not correct about energy changes?
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(D)
ΔH at 298 K is the activation energy
28
f 5.0 cm\(^-3\) of 0.200 mol dm(^-3\) Na\(_2\)CO\(_3\) was diluted to 250cm(^-3\) solution, what would be the concentration of the resulting solution?
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(A)
0.004 mol dm(^-3\)
29
The initial volume and pressure of a given mass of gas is V and 3.P. What is its pressure if its volume is increased to 2V at constant temperature?
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(C)
\(frac{3}{2}\) P
30
What volume of oxygen at s.t.p is required to burn completely 7.5 dm\(^3\) of methane according to the following equation?
When 250 cm3 of a saturated solution of CuSO\(_4\) at 30°C was evaporated to dryness, 5.0 g of the salt was obtained..
What is the solubility of the salt at 30°C? [CuSO\(_4\) = 160]
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(B)
0.125
32
The bond between NH\(_3\) and H\(^+\) in NH4\(^+\) is?
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(A)
dative
33
Which of the following oxides has a giant covalent structure?
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(D)
SiO\(_2\)
34
Which of the following hydroxides is not readily soluble in water?
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(B)
Ca(OH)\(_2\)
35
Which of the following statements about the solubility of a salt is correct?
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(C)
Crystallization would be efficient in separating out a salt whose solubility increases considerably with temperature
36
How many moles of H\(_2\)SO4 are there in 50 cm\(^3\) of 0.108 mol dm\(^3\) solution of the acid?
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(B)
5.4 x 10\(^{-3}\)
37
If 20 cm\(^3\) of sodium hydroxide was neutralized by 20 cm\(^3\) of 0.01 mol dm\(^3\) tetraoxosulphate(VI) acid, what is the concentration of the sodium hydroxide solution?
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(B)
0.020
38
"Electrons always occupy the lowest empty energy level" is a statement of
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(A)
Aufbau Principle
39
Which of the following metals does not react with water to produce hydrogen?
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(A)
Copper
40
Which of the following arrangement of elements is in decreasing order of electronegativity?
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(D)
P, Si, Al, Mg, Na
41
The metallic bond in magnesium is stronger than that in calcium because magnesium has a
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(B)
smaller atomic size
42
Consider the reaction represented by the following equation:
AgNO\(_3\) + NaCl → AgCl + NaNO\(_3\).
The steps that could be taken to obtain pure dry sample of AgCI (s) from the mixture includes
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(C)
filtering, washing and drying
43
How many electrons does \({31}_{15}\)P\(^3-\) contain?
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(D)
18
44
The atomic number of an atom would be equal to its mass number if it
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(C)
does not contain neutrons
45
Which of the following processes is not exhibited by atoms in order to attain more stable electron configuration?
