Chemistry is the study of the substances that make up matter. It looks at their properties, how they react with each other, and how these reactions can create new substances.
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Question 121: Which of the following statement is true of a proton?
Options:
A) The mass of a proton is 1840 times the mass of electron
B) the total mass of the protons in a particular nucleus is always half the nuclear size
C) The mass of a proton is one - twelfth the molar mass of carbon
D) The mass of a proton is 1.0008g
Show Answer
The correct answer is D .
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Question 122:
How many moles of limestone will be required to produce 5.6g of CaO?
[Ca = 40, C = 12, O= 16]
Options:
A) 0.20 mol
B) 0.10 mol
C) 1.12 mol
D) 0.56 mol
Show Answer
The correct answer is B .
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Question 123:
An organic compound contains 69% carbon, 15.3% hydrogen and 30.7% oxygen. Calculate the the empirical formula [C=12, H = 1, O = 16]
Options:
A) CHO
B) CHO
C) CHO
D) CHO
Show Answer
The correct answer is D .
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Question 124:
Calculate the volume in cm3 of oxygen evolved as s.t.p. when a current of 5 A is passed through acidified water for 193s
{F = 96500 Cmol-1, Molar volume of a gas at s.t.p. = 22.4 dm3}
Options:
A) 224.000 dm3
B) 0.056 dm3
C) 0.224 dm3
D) 56.000 dm3
Show Answer
The correct answer is B .
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Question 125:

The option above shows the PH changes for the titration of a
Options:
A) strong acid versus strong base
B) weak acid versus strong base
C) strong acid versus weak base
D) weak acid versus weak base
Show Answer
The correct answer is A .
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Question 126: In a water body, too much sewage leads to
Options:
A) a decrease in the temperature of the water which cause in death of aquatic animals
B) an increase in the number of aquatic animals in the water
C) an increase in the bacterial population which reduces the level of oxygen in the water
D) a decrease in the bacterial population which increases the level of oxygen in the water
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The correct answer is C .
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Question 127:
2X(aq) + MnO2(s) + 4H+(aq) → X2(g) + Mn2+(aq) + 2H2O.
The reaction above can be used for the laboratory preparation of all halogens except fluorine because it is?
Options:
A) a poisionous gas
B) an oxidizing agent
C) electronegative in nature
D) highly reactive
Show Answer
The correct answer is D .
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Question 128: Water is poured over a white solid and a colourless neutral gas is evolved which burns with a sooty flame. The white solid is?
Options:
A) calcium
B) calcium oxide
C) calcium carbide
D) sodium peroxide
E) sodium sulphate
Show Answer
The correct answer is C .
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Question 129: Geometric isomerism can exist in
Options:
A) hex-3-ene
B) hexane
C) prop-l-ene
D) 3-methyl but -l-ene
Show Answer
The correct answer is A .
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Question 130:
Which of the following reactions would be expected to have the highest entropy change?
Options:
A) Liquid → Gas
B) Solid → Liquid
C) Gas → Liquid
D) Gas → Solid
Show Answer
The correct answer is A .