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 741: Hydrogen diffuses through a porous plug
Options:
A) at the same rate as oxygen
B) at a slower rate than oxygen
C) twice as fast as oxygen
D) three times as fast as oxygen
E) four times as fast as oxygen
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The correct answer is E .
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Question 742:
The tabulated results below were obtained by titration 10.0 cm3 of water with soup. The titration was repeated with the same sample of water after boiling. The ratio of permanent to temporary hardness is
Options:
A) 1.5
B) 1.4
C) 4.1
D) 5.1
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The correct answer is C .
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Question 743:
Which of the following factors does NOT affect the rate of a chemical reaction?
Options:
A) Concentration of reactants
B) Presence of a catalyst
C) Molecular weight of products
D) Temperature
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The correct answer is C .
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Question 744: A hydrated salt of formula MSO4.xH2 O CONTAINS 45.3% by mass of water of crystalisation. Calculate the value of x [M = 56, S = 32, O = 16, H = 1 ]
Options:
A) 3
B) 5
C) 7
D) 10
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The correct answer is C .
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Question 745: Crude copper could be purified by the electrolysis of concentrated copper (II) chloride if the crude copper is?
Options:
A) made both the anode and the cathode
B) made the cathode
C) made the anode
D) dissolved in the solution
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The correct answer is C .
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Question 746: The removal of rust from iron by treatment with tetraoxosulphate (IV) acid is based on the?
Options:
A) hydrolysis of the iron
B) reaction of acid with base
C) oxidationof the rust
D) dehydration of the iron
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The correct answer is D .
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Question 747: Which of the following is used to study the arrangement of particles in crystal lattices?
Options:
A) Alpha-particles
B) Beta-particles
C) Gamma-rays
D) X-rays
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The correct answer is D .
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Question 748:
In the electrolysis of aqueous solution of K2SO 4 in the above cell, which species migrate to the anode?
Options:
A) SO2-OH -
B) K + and SO 42-
C) OH and HO
D) H3O + and K
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The correct answer is A .
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Question 749: Beryllium and aluminium have similar properties because they
Options:
A) are both metals
B) belong to the same group
C) belong to the same period
D) are positioned diagonally to each other
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The correct answer is D .
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Question 750: Mortar is NOT used for under-water construction because
Options:
A) it hardens by lose of water
B) its hardening doe not depend upon evaporation
C) it requires concrete to harden
D) it will be washed away by the flow of water
Show Answer
The correct answer is A .