11 mark
What is the mass of 0.56 moles of potassium dichromate (VI), K2Cr2O7?
79.52 g
164.75 g
525.36 g
155.79 g
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Syllabus Edition
First teaching 2023
First exams 2025
|
The Mole & the Avogadro Constant (CIE A Level Chemistry)
Topic Questions
21 mark
Ethane has the formula C2H6.
What is the mass in grams of one molecule of ethane? (Ar: C = 12.0; H = 1.0)
(the Avogadro constant L = 6.023 x 1023)
1.81 x 1025
5.00 x 10-23
30.0
3.00 x 10-23
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31 mark
How many molecules of nitrogen gas are in 4.00 g?
(the Avogadro constant L = 6.023 x 1023)
8.61 x 1022
4.22 x 1024
6.75 x 1025
1.75 x 1023
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11 mark
Which of these substances contains the greatest number of atoms?
113 mg of chlorine
1.32 × 10-4 kg of sulfur
92.0 mg of ammonia
1.69 × 10−4 kg of methane
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21 mark
A gas cylinder for a portable heater contains 13 kg of butane.
How many butane molecules are in the gas cylinder?
The Avogadro’s constant, L = 6.022 x 1023 mol-1
1.35 x 1026
2.69 x 1024
1.40 x 1026
3.72 x 10-22
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3
1 mark
1 markWhich mass of substance contains the greatest number of atoms?
3.00 g of ammonia
3.00 g of chloromethane
4.00 g of hydrogen sulfide
4.00 g of hydrogen chloride
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11 mark
The mass of a coin is 20% nickel. The coin has a mass of 10.0 g.
How many nickel atoms are in the coin?
4.30 x 1022
1.03 x 1023
1.20 x 1024
2.05 x 1022
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21 mark
A coin contains 5.921% nickel by mass. If the coin weighs 9.97 g, how many nickel atoms are in the coin?
4.30 x 1022
3.01 x 1023
6.02 x 1025
6.02 x 1021
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31 mark
1 markWhich sample contains the greatest number of molecules?
1 g of methanal, CH2O
2 g of carbon dioxide, CO2
3 g of sulfur, S6
4 g of bromine, Br2
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