Topic 9
The Periodic Table:
Chemical Periodicity
Topic 9 follows Period 3 from sodium to argon. The periodic trends page covers atomic and ionic radius, melting point, conductivity and ionisation energy (9.1). Five new pages cover the chemistry of the elements and their compounds (9.2): the reactions of the elements with oxygen, chlorine and water and the oxidation numbers of the oxides and chlorides; the structure, bonding and melting points of the oxides; their behaviour with water, acids and bases, including the amphoteric Al₂O₃ and Al(OH)₃; the chlorides with water and deducing bonding from properties; and predicting the properties and position of unknown elements (9.3).
Revision Notes
8 revision notes, in the order the specification teaches them.
9.1 Periodic Trends
Atomic radius, ionisation energy, melting point and conductivity across Period 3 explained by structure and bonding (9.1.1, 9.1.2).
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Atomic and Ionic Radii (Topic 1)
The periodicity of atomic and ionic radius across Radii, including the isoelectronic ions (9.1.1-a, 9.1.1-b), on the Topic 1 pages.
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Ionisation Energy (Topic 1)
The ionisation energy trends across Period 3 and down a group, on the Topic 1 pages (1.4.3).
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Reactions of Period 3 Elements with Oxygen, Chlorine and Water
The reactions of Period 3 elements with oxygen, chlorine and water: equations, observations and trends.
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Period 3 Oxides: Structure, Bonding and Melting Points
The structures and bonding of the Period 3 oxides and the trend in their melting points.
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Period 3 Oxides with Water, Acids and Bases
The reactions of Period 3 oxides with water, acids and bases, the pH of the solutions and the trend from basic to acidic oxides.
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Period 3 Chlorides and Deducing Bonding from Properties
The reactions of Period 3 chlorides with water and on deducing the type of bonding in oxides and chlorides from their properties.
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Predicting the Properties of Unknown Elements
Predicting the properties of an element from its group and deducing the identity and position of unknown elements from their properties.
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Ionisation Energies Map
Cambridge International AS & A Level Chemistry · Topic 1 Ionisation energy and 9.1 Period 3
The whole section on one A4 page: ionisation energies and their four factors, successive IEs, trends, and Period 3 melting points and conductivity.
Periodicity Map
Cambridge International AS & A Level Chemistry · Topic 9 The Periodic Table: chemical periodicity
All of Topic 9 on one A4 page: Period 3 reactions, oxidation numbers, oxides and chlorides with water, bonding and predicting properties.
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9.1.1
- a
describe qualitatively (and indicate the periodicity in) the variations in atomic radius of the elements in Period 3
Revise - b
describe qualitatively (and indicate the periodicity in) the variations in ionic radius of the elements in Period 3
Revise - c
describe qualitatively (and indicate the periodicity in) the variations in melting point of the elements in Period 3
Revise - d
describe qualitatively (and indicate the periodicity in) the variations in electrical conductivity of the elements in Period 3
Revise
9.1.2
- b
explain the variation in electrical conductivity in terms of the structure and bonding of the elements
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9.2.1
9.2.2
- a
state and explain the variation in the oxidation number of the oxides (Na2O, MgO, Al2O3, P4O10, SO2 and SO3 only) in terms of their outer shell (valence shell) electrons
Revise - b
state and explain the variation in the oxidation number of the chlorides (NaCl, MgCl2, AlCl3, SiCl4, PCl5 only) in terms of their outer shell (valence shell) electrons
Revise
9.2.3
- a
describe, and write equations for, the reaction, if any, of the oxide Na2O with water including the likely pH of the solution obtained
Revise - b
describe, and write equations for, the reaction, if any, of the oxide MgO with water including the likely pH of the solution obtained
Revise - c
describe, and write equations for, the reaction, if any, of the oxide Al2O3 with water including the likely pH of the solution obtained
Revise - d
describe, and write equations for, the reaction, if any, of the oxide SiO2 with water including the likely pH of the solution obtained
Revise - e
describe, and write equations for, the reaction, if any, of the oxide P4O10 with water including the likely pH of the solution obtained
Revise - f
describe, and write equations for, the reaction, if any, of the oxide SO2 with water including the likely pH of the solution obtained
Revise - g
describe, and write equations for, the reaction, if any, of the oxide SO3 with water including the likely pH of the solution obtained
Revise
9.2.4
- c
describe, explain, and write equations for, the acid/base behaviour of the oxide Al2O3, including amphoteric behaviour in reactions with acids and bases (sodium hydroxide only)
Revise - i
describe, explain, and write equations for, the acid/base behaviour of the hydroxide Al(OH)3, including amphoteric behaviour in reactions with acids and bases (sodium hydroxide only)
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9.2.5
- a
describe, explain, and write equations for, the reaction of the chloride NaCl with water including the likely pH of the solution obtained
Revise - b
describe, explain, and write equations for, the reaction of the chloride MgCl2 with water including the likely pH of the solution obtained
Revise - c
describe, explain, and write equations for, the reaction of the chloride AlCl3 with water including the likely pH of the solution obtained
Revise - d
describe, explain, and write equations for, the reaction of the chloride SiCl4 with water including the likely pH of the solution obtained
Revise - e
describe, explain, and write equations for, the reaction of the chloride PCl5 with water including the likely pH of the solution obtained
Revise
9.2.6
- 9.2.6
explain the variations and trends in 9.2.2, 9.2.3, 9.2.4 and 9.2.5 in terms of bonding and electronegativity
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9.2.7
9.3.1
- 9.3.1
predict the characteristic properties of an element in a given group by using knowledge of chemical periodicity
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9.3.2
- 9.3.2
deduce the nature, possible position in the Periodic Table and identity of unknown elements from given information about physical and chemical properties
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