Sacred Heart Canossian College (English Section)
Subject: Chemistry
Revision Worksheet
2nd term 2021-2022
Name:_________________________________________________________ Class No.:_________
Date:___________________
Ch. 2 – The atmosphere
1. A mixture of alcohol and water is to be separated. The following table shows the boiling points of
the components in the mixture.
Component Boiling point (°C)
Methanol
64.7
Ethanol
78
Water
100
Octanol
195
(a) Ethanol has a formula of CH3CH2OH. Is it an element or compound or mixture? Explain your choice.
(b) Which substance will be distilled out of the mixture last? Explain.
(c) State the name of the process used to separate the components in the mixture.
(d) Draw an experimental setup for the process stated in (c).
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Ch. 4 – Rocks and Minerals
1. The following question is about calcium-containing compounds.
Add carbon dioxide
Limestone
_________________
Thermal
decomposition
_________________
Add
water
Limewater
Filtration
(a) Fill in the blanks with the common names of the calcium-containing compounds in the above
diagram.
(b) Write a word equation for the thermal decomposition of limestone.
(c) Write a word equation for the conversion of limewater to limestone.
Ch. 7 – Chemical bonding
1. This question is about ionic compounds. For each of the following,
(i) state the name of the ionic compound
(ii) formula of the ionic compound
(iii) colour of the ionic compound
(iv) dot-and-cross diagram to show the formation of the ionic compound
(a) calcium and phosphide
(b) aluminium and nitrogen
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Ch. 10 – Occurrence and extraction of metals
1. For the following ores state
(i) The method of extraction you would use to extract the metal.
(ii) Write the word equations with respect to this method of extraction.
(a) Zinc blende (ZnS)
(b) Potash (KCl)
Ch. 12 – Mole calculations
1. Identify the number of mol of atoms/ions/cations/anions applicable to the substances stated
below.
E.g. 0.5 mol of sodium chloride contains
0.5 mol NaCl x
2 mol atoms
1 mol NaCl
= 1 mol atoms
2 mol ions
0.5 mol NaCl x 1 mol NaCl = 1 mol ions (NOTE: not all substance consist of ions/cations/anions)
0.5 mol NaCl x
1 mol cation
0.5 mol NaCl x
1 mol anion
1 mol NaCl
1 mol NaCl
= 0.5 mol cation (Na+)
= 0.5 mol anion (Cl-)
(a) 2 mol of chlorine gas contains
(b) 0.3 mol of lithium oxide contains
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(c) 5 mol of sulphur dioxide contains
(d) 1.5 mol of calcium hydroxide contains
2. Calculate the following quantities:
(a) The mass of magnesium chloride in 1.5 mol.
(b) The number of moles of ions in 1.204 x 1024 of sodium chloride compounds.
1.204 x 1024 NaCl compound x
1
mol NaCl
6.02 x 1023 NaCl compound
x
mol ions
mol NaCl
=
(c) The number of moles of atoms in 3.762 x 1022 of carbon dioxide molecules.
(d) The mass in 3.01 x 1023 water molecules.
3.01 x 1023 H2O molecules x
1
6.02 x 1023
mol H2 O
H2 O molecule
x
g H2 𝑂
mol H2 O
=
(e) The mass in 3.612 x 1022 copper(II) chloride compounds.
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(f) In 30 g of potassium carbonate, calculate
(i) the total number of compounds,
30 g K2CO3 x
1
mol K2 CO3
g K2 CO3
K2 CO3 compound
x
mol K2 CO3
=
(ii) the number of moles of atoms,
(iii) the number of moles of ions.
Ch. 13 – Corrosion of metals and their protection
1. For the following test tubes, state which test tube will the iron nail rust most rapidly. Explain your
reasoning.
tap water
tap water
salt solution
sugar solution
iron nail
wrapped with
tin wire
iron nail
wrapped with
zinc wire
iron nail
wrapped with
tin wire
iron nail
wrapped with
tin wire
Test tube #1
Test tube #2
Test tube #3
Test tube #4
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2. The following diagram shows three Petri dishes with three different pairs of metal wires.
iron
wire
silver
wire
Dish A
iron
wire
iron
wire
iron
wire
zinc
wire
Dish B
Dish C
(a) Arrange the rate of rusting of the iron wire in each dish in ascending order.
(b) Explain your reasoning to the arrangement you proposed above.
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