Chemistry study notes
The Periodic Table
Explain trends from electrons and structure, then predict the oxides, chlorides and redox behaviour of unfamiliar elements.
A-Level 9476 (2026-2027)
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6 topicsElectronic structure and atomic trends
Compare radius, ionisation energy and electronegativity across and down.
Melting, conduction and volatility
Use the actual particles and bonding in the elements.
Period-3 oxides and hydroxides
Track oxidation numbers, reactions with water and acid-base behaviour.
Period-3 chlorides in water
Distinguish dissolution, hydrated-ion hydrolysis and molecular hydrolysis.
Group 2 and Group 17 chemistry
Use electrode potentials and explain thermal stability.
Predict and identify
Combine independent physical and chemical clues.
Scope
Learning outcomes
5. The Periodic Table. Use the outcome map to find the explanation for a particular syllabus requirement.
See the learning outcome map
5(a) Recognise electronic-configuration patterns.
- Period 3 Na-Cl
- Group 2 Mg-Ba
- Group 17 Cl-I
5(b) Explain atomic and ionic size, first IE and electronegativity trends.
- (i) Across a period: shielding and nuclear charge
- (ii) Down a group: shell number, shielding and nuclear charge
- Subshell/pairing variations and isoelectronic ions
5(c) Interpret melting and conductivity across the period.
- Metallic elements
- Giant molecular silicon
- Simple molecular phosphorus, sulfur and chlorine
5(d) Explain halogen volatility.
- Cl2, Br2, I2
- Instantaneous dipole-induced dipole attraction
- Polarizability, not X-X bond breaking
5(e) Explain the specified oxide and chloride patterns.
- (i) Highest oxidation numbers: Na2O, MgO, Al2O3, SiO2, P4O10, SO3; NaCl, MgCl2, AlCl3, SiCl4, PCl5
- (ii) Electronegativity and bonding, with AlCl3 treated separately
- (iii) Water reactions of all six oxides
- (iv) Acid/base behaviour of all six oxides and NaOH, Mg(OH)2, Al(OH)3; amphoteric reactions with acids and NaOH
- (v) Water reactions of all five chlorides
- (vi) Infer oxide/chloride structure from physical and chemical observations
Highest oxides progress from ionic bases to covalent acidsAmphoteric aluminium compounds react on both sidesDissolving a chloride is not always the same as hydrolysing it
5(f) Use standard potentials to compare reactivity.
- (i) Group 2 reducing agents
- (ii) Group 17 oxidising agents
- Written half-reaction direction and standard conditions
5(g) Explain thermal-stability trends.
- (i) Group 2 carbonates: cation charge density and anion polarizability
- (ii) Group 17 hydrides: covalent bond energies
5(h) Predict properties from group membership.
- Transfer known periodic mechanisms to another member of a specified group
5(i) Infer periodic position and identity from evidence.
- Physical and chemical properties
- Nature and likely position
- Check whether the evidence establishes a unique identity