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 701: Calculate the mass, in kilograms, of magnesium produced by the electrolysis of magnesium (II) chloride in a cell operating for 24 hours at 500 amperes.
Options:
A) 2.7
B) 5.4
C) 10.8
D) 21.7
Show Answer
The correct answer is B .
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Question 702: When air is compressed?
Options:
A) its density decreases
B) it solidifies
C) its temperature decreases
D) its temperature increases
E) its temperature remains unchanged
Show Answer
The correct answer is C .
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Question 703: Which of the following gases will rekindle a brightly glowing splint?
Options:
A) NO2
B) NO
C) N2O
D) CI2
Show Answer
The correct answer is C .
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Question 704: A compound contains 40.0% carbon, 6.7% hydrogen and 53.3% oxygen. If the molar mass of the compound is 180, Find the molecular formula [H = 1, C = 12, O = 16)
Options:
A) CH2O
B) C3H6O3
C) C6H12O6
D) C6H12O3
Show Answer
The correct answer is C .
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Question 705: The oxidation state of chlorine in potassium chlorate is
Options:
A) +1
B) +2
C) +3
D) +5
E) +7
Show Answer
The correct answer is D .
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Question 706:
56.00cm3 of a gas at S.T.P. weighed 0.11g. What is the vapour density of the gas?
[Molar volume of a gas at S.T.P = 22.4dm3]
Options:
A) 11.00
B) 22.00
C) 33.00
D) 44.00
Show Answer
The correct answer is B .
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Question 707: A constituent common to bronze and solder is
Options:
A) lead
B) silver
C) copper
D) tin
Show Answer
The correct answer is D .
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Question 708: In the laboratory preparation of oxygen, dried oxygen is usually collected over
Options:
A) hydrochloric acid
B) mercury
C) calcium chloride
D) tetraoxosulphate (VI) acid
Show Answer
The correct answer is B .
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Question 709: Safety matches contain sulphur and?
Options:
A) potassium trioxochlorate (V)
B) potassium trioxonitrate (V)
C) charcoal
D) phosphorus sulphide
Show Answer
The correct answer is D .
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Question 710:
C2H5OH(aq) → Y
If the above reaction takes place in conc. H2SO4 at 180o, Y represents
Options:
A) CH4
B) C2H5COOH
C) C2H4
D) CH3OCH3
Show Answer
The correct answer is C .