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 611: The chromatography separation of ink is based on the ability of the components to
Options:
A) React with solvent
B) React with each other
C) Dissolve in each other in the column
D) Move at different speeds in the column
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The correct answer is D .
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Question 612: The alloy duralumin is used for the building of aeroplanes because it?
Options:
A) asborbs heat readily from sure thereby preventing the inside of the plane from getting cold at high attitudes
B) reflects sunlight readily, thereby keeping the inside of the plane cool
C) is extremely durable and possesses reflective ability
D) is easily the lightest building material
E) possesses both strenght and lightness
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The correct answer is E .
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Question 613: Oil spillage in ponds and creeks can be cleaned up by?
Options:
A) burning off the oil layer
B) spraying with detergent
C) dispersal with compressed air
D) spraying with hot water
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The correct answer is B .
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Question 614:
The choice of method for extracting a metal from its ores depends on the
Options:
A) strength of the core
B) position of the metal in the electrochemical series
C) source of the core
D) position of the metal in the periodic table
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The correct answer is B .
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Question 615: A mixture of sand, ammonium chloride and sodium chloride is best separated by?
Options:
A) sublimation followed by addition of water and filteration
B) sublimation followed by addition of water and evaporation
C) addition of water followed by filtration and sublimation
D) addition of water followed by crystallization and sublimation
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The correct answer is A .
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Question 616:
Elements P, Q, R, S have 6, 11, 15, 17 electrons respectively, therefore,
Options:
A) P will form an electrovalent bond with R
B) Q will form a covalent bond with S
C) R will form an electrovalent bond with S
D) Q will form an electrovalent bond with S
E) Q will form a covalent bond with R
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The correct answer is D .
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Question 617:
The situation obtained when a perfect gas expands into a vacuum is
Options:
A) ΔH is positive and TΔ S is zero
B) ΔH is positive and T Δ S is negative
C) ΔH is negative and TΔ S is zero
D) ΔH is zero and T Δ S is positive
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The correct answer is D .
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Question 618: Certain useful waxes are composed mainly of
Options:
A) amino acids
B) glycerols
C) alkanols
D) alkanoates
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The correct answer is B .
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Question 619:
C12H22O11(s) + H2SO4(aq) 12C(s) + 11H2O(l) + H2SO4(aq)
In the reaction above, tetraoxosulphate (VI) acid function as
Options:
A) A dehydrate agent
B) An oxidizing agent
C) A reducing agent
D) A catalyst
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The correct answer is A .
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Question 620:
16.8 g of sodium hydrogen trioxocarbonate (IV) is completely decomposed by heat. Calculate the volume of carbon(IV) oxide given off s.t.p
[Na 23, C = 12, O = 16, H = 1, Molar volume of a gas at s.t.p = 22.4 dm3]
Options:
A) 22.40 dm3
B) 11.20 dm3
C) 2.24 dm3
D) 1.12 dm3
Show Answer
The correct answer is C .