What is the solubility of a salt if 0.4g of it is obtained on evaporating 200\(cm^{3}\) of its saturated solution to dryness?
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(B)
2.00\(gdm^{-3}\)
6
An acidic salt has
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(C)
hydrogen ions in its aqueous solution
7
A reaction is endothermic if the
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(A)
reaction vessel feels cool during the reaction
8
In which of the following compounds does hydrogen form ionic compounds?
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(D)
NaH
9
An organic compound has the empirical formula \(CH_{2}\). If its molar mass is 42\(gmol^{-1}\), what is its molecular formula? (C = 12.0, H = 1.0)
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(C)
\(C_{3}H_{6}\)
10
Consider the following reaction equation: \(Br_{2} + 2KI \to 2KBr + I_{2}\). Bromine is acting as
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(A)
an oxidizing agent
11
Ethene is produced from ethanol by
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(D)
dehydration
12
Consider the following equilibrium reaction: \(2AB_{{2}{(g)}} + B_{{2}{(g)}} \to 2AB_{{3}{(g)}}\). \(\Delta H= -X kJmol^{-1}\). The backward reaction will be favored by
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(A)
a decrease in pressure
13
What is the mass of solute in 500\(cm^{3}\) of 0.005\(moldm^{-3}\) \(H_{2}SO_{4}\)? ( H = 1, S = 32.0, O=16.0)
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(C)
0.245g
14
Pure water can be made to boil at a temperature lower than 100°C by
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(B)
decreasing the external pressure
15
At what temperature does the solubility of \(KNO_{3}\) equal that of \(NaNO_{3}\)?
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(B)
20°C
16
When a salt is added to its saturated solution, the salt
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(C)
precipitates and the solution remains unchanged
17
When substance X was added to a solution of bromine water, the solution became colourless. X is likely to be
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(C)
propyne
18
The preferential discharge of ions during electrolysis is influenced by the
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(C)
nature of the electrode
19
The valence electrons of \(_{12}Mg\) are in the
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(A)
3s orbital
20
Stainless steel is an alloy comprising of
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(C)
Fe, C and Ni
21
The number of Hydrogen ions in 1.0\(dm^{3}\) of 0.02\(moldm^{-3}\) tetraoxosulphate(VI) acid is \([N_{A} = 6.02 \times 10^{23}]\)
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(A)
\(1.2 \times 10^{22}\)
22
The most suitable substance for putting out petrol fire is
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(B)
carbon(IV) oxide
23
The following factors would contribute to environmental pollution except
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(C)
photosynthesis
24
The position of equilibrium in a reversible reaction is affected by
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(D)
change in concentration of the reactants
25
The diagram above illustrates a conical flask containing water and ice. Which of the following is correct about the diagram?
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(B)
Energy is absorbed when the ice changes to water
26
Which of the following statements best explains the difference between a gas and a vapour?
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(B)
Unlike gases, vapour can easily be condensed into liquids
27
Consider the following reaction equation: \(2HCl + Ca(OH)_{2} \to CaCl_{2} + H_{2}O\). What is the volume of 0.1\(moldm^{-3}\) HCl that would completely neutralize 25\(cm^{3}\) of 0.3\(moldm^{-3}\) Ca(OH)\(_{2}\)?
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(A)
150\(cm^{3}\)
28
\(Cu\) and \(HNO_{3}\) are not suitable for preparing hydrogen gas because of their
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(A)
reactivity and oxidation respectively
29
Which of the following CANNOT be an empirical formula?
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(D)
\(N_{2}O_{4}\)
30
One of the criteria for confirming the purity of benzene is to determine its
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(B)
boiling point
31
When chlorine is passed through a sample of water, the pH of the water sample would be
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(A)
< 7
32
How many atoms are contained in 0.2moles of nitrogen? \([N_{A} = 6.02 \times 10^{23}]\)
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(A)
\(1.20 \times 10^{23}\)
33
The strength of metallic bonds depends on the
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(C)
number of valence electrons
34
When zinc is added to AgNO\(_{3}\) solution, crystals of silver forms on the zinc surface. This indicates that zinc is
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(A)
oxidised
35
The empirical formula of a compound containing 0.067mol Cu and 0.066mol O is [Cu = 63.5, O = 16]
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(B)
\(CuO\)
36
The change in the oxidation state of iron in the reaction represented by the equation: \(2FeCl_{3} + H_{2}S \to 2FeCl_{2} + 2HCl + S\) is
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(C)
+3 to +2
37
Which of the following methods can be used to seperate blood cells from plasma?
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(A)
Centrifugation
38
Which of the following statements is true about ionic radius? Ionic radius
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(B)
decreases as nuclear charge increases
39
Analysis of a hydrocarbon shows that it contains 0.93g of Carbon per gram of the compound. The mole ratio of carbon to hydrogen in the compound is [H = 1.0, C=12.0]
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(A)
1:1
40
The law of definite proportions states that
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(A)
pure samples of the same compound contain the same elements combined in the same proportion by mass
41
What is the relative molecular mass of a compound which has empirical formula \(CH_{2}O\)? [C= 12, H= 1, O= 16]
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(D)
180
42
Atoms are electrically neutral because they
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(B)
contain equal number of protons and electrons
43
Common Salt (NaCl) is used to preserve foods. Which of the following properties can be used to determine its purity before use?
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(B)
Melting point
44
Which of the following electron configurations represents the transition element Chromium \(_{24}Cr\)?
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(D)
\(1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{1}3d^{5}\)
45
The atomic number of an isotope of hydrogen is equal to its mass number because it
