The periodic table is an arrangement of elements according to their?
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(B)
Atomic number
2
A solid with higher melting and boiling points is likely to be?
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(C)
An Electrovalent compound
3
Which of the following metals reacts slowly with cold water?
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(C)
Calcium
4
which of the following elements has the highest ionization energy?
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(C)
Flourine
5
The bleaching action of chlorine is through the process?
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(D)
Oxidation
6
If 6.5g of magnesium ribbon reacts completely with Hydrochloric acid, how many grams of hydrogen gas would be liberated?
Mg(s) + 2 HCl(aq) --> MgCl 2(aq) + H 2(g)
[ H = 1.0, Mg = 24.0 ]
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(A)
0.54g
7
Calcium and magnesium belong to the group of the periodic table because both?
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(D)
have same number of valence electrons
8
Which of the substances is non-polar?
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(A)
Bromine
9
Which of the following pairs of components have the same molecular mass?
[ H = 1.0, C = 12.0, O = 16.0 ]
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(C)
Carbon (ii) Oxide and Ethene
10
When an equilibrium is established between dissolved and undissolved solutes, the solution is said to be?
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(A)
Saturated
11
How many moles of carbon(iv)oxide contains 16.0g of oxygen?
[ C = 12.0, O = 16.0 ]
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(D)
0.50 mol
12
Stoichiometry is based on the law?
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(D)
conservation of mass
13
What is the percentage by mass of H in CH\(_3\)COOH ?
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(C)
6.7%
14
Which of the following compounds has coordinate bonds in its structure?
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(A)
Al\(_2\)Cl\(_6\)
15
The name of the compound CH\(_3\)C(CH\(_3\))\(_2\)CH\(_2\)CH\(_2\)CH\(_3\)
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(D)
2,2 - dimethyl pentane
16
The properties of a good primary standard solution include the following except?
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(B)
low molecular mass
17
What is the solubility of a salt X at 25ºC if the saturated solution of the salt contains 0.28g in 100cm\(^3\) of the solution in mol\dm\(^3\)?
[ X = 56.0g ]
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(A)
0.05
18
Vinegar is an aqueous solution of?
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(C)
ethanoic acid
19
which of the following solutions containing one mole per dm\(^3\) of the compound would have the lowest PH?
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(B)
hydrochloric acid
20
A sample of air was bubbled into water. The PH of the water slowly changed from 7 to 6. Which of the following gases in the samples caused the change?
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(A)
carbon(iv)oxide
21
The most suitable indicator for the reaction between NaOH and HCOOH is?
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(D)
phenolphthalein
22
consider the following reaction equation: 2Al(OH)\(_3\) + 3H\(_2\)SO\(_4\) →Al\(_2\)(SO4)\(_3\)(aq)+6H\(_2\)O. How many moles of tetraoxosulphate(vi)acid is needed to produce 0.5mol of aluminium tetraoxosulphate(vi)?
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(C)
1.5
23
which of the following pairs of substances has the highest heat of neutralization?
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(A)
strong acid and strong base
24
When quicklime dissolves in water?
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(B)
heat is evolved
25
If the value of ΔH is positive for a reaction, it means that the reaction is?
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(B)
endothermic
26
Which of the following compounds is formed by the oxidation of ethanol?
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(D)
CH\(_3\)CO\(_2\)H
27
What is the characteristic of the gas liberated when dilute hydrochloric acid is added to Iron(ii)sulphide?
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(D)
turns lead(ii)ethanoate paper black
28
An organic compound contains 72% carbon, 12% hydrogen and 16% oxygen by mass. What is the empirical formula of the compound?
[ H = 1.0. C = 12.0, O = 16.0 ]
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(B)
C\(_6\)H\(_{12}\)O
29
When excess chlorine is mixed with ethane at room temperature, the product formed is?
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(A)
1,2-dichloroethane
30
which of the following reagents could be used to distinguish between propan-1-ol and propan-2-ol
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(A)
H+ / K2Cr2O7
31
If a catalyst is added to a system, the temperature and the pressure remain constant, there would be no effect on the?
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(D)
heat of reaction
32
consider the following reaction equation: 2NH\(_3 \) .+ 3Cl\(_2\) → N2 + 6HCl.
NH\(_3\) is acting as?
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(A)
a reducing agent
33
The oxidation of chromium in Cr\(_2\)O\(_7)\(-2\) ?
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(C)
+6
34
The process by which alkanoic acid reacts reversibly with alkanols is known as?
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(B)
esterification
35
If the oxidation potential of Mg and Al are +2.37 volts and + 1.66 volts respectively, then the Mg would?
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(D)
replace Al
36
consider the reaction represented by the following equation: 2SO\(_2\) + O\(_2\) ⇌ 2SO\(_3\)
A decrease in the pressure of the reaction would
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(C)
shift the equilibrium position to the left
37
In a mixture of gases which do not react chemically together, the pressure of the individual gas is?
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(D)
partial pressure
38
Biotechnology is applied in the?
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(A)
treatment of sewage
39
which of the following organic compounds has the lowest boiling point?
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(D)
( CH\(_3\) )\(_3\)
40
Consider the following reaction represented by the following equation:
C\(_2\)H\(_2\) \(^{H_2}_{→}\) X \(^{H_2}_{→}\) Y. X and Y respectively are?
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(B)
ethene and ethane
41
Which of the following substances can be classified as heavy chemicals?
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(B)
H\(_2\)SO\(_4\)
42
in Boyle's law?
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(D)
T is constant, V varies inversely with P
43
Which of the following apparatus is NOT used in volumetric analysis?
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(C)
Desiccator
44
One of the deductions from Rutherford's alpha particle scattering experiment is that?
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(C)
nuclei of atoms are positively charged
45
The atoms of \(^{64}_{29}\)Cu and \(^{65}_{30}\)Zn have the same number of?
