S3.1 Periodicity
Learning Objectives
3.1.1 & 3.1.2: Groups on the Periodic Table: Classify elements according to their position in the periodic table (groups, periods, blocks) and type (metals, non-metals, metalloids). Identify key groups such as alkali metals, alkaline earth metals, transition metals, halogens, and noble gases.
3.1.3: Periodic Trends: Describe and explain trends in atomic radius, ionic radius, ionization energy, electron affinity, and electronegativity across periods and down groups using concepts such as nuclear charge, shielding, and energy levels.
3.1.4 & 3.1.5: Metallic Character and Oxides: Identify trends in metallic character. Write equations for reactions of metals and non-metals with water and deduce whether the oxides formed are acidic or basic.
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3.1.6: Oxidation States: Determine oxidation states using standard rules, including exceptions. Apply oxidation number rules to elements in compounds and polyatomic ions.
Higher Level
3.1.7: Discontinuities in Ionization Energy (HL):
Explain anomalies in ionization energy trends using electronic structure, specifically sublevel energy differences and electron repulsion, with reference to groups 2→3 and 15→16.
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3.1.8: Properties of Transition Elements (HL):
Define a transition element. Describe the typical properties of transition metals, including variable oxidation states, formation of colored compounds, catalytic activity, and magnetic behavior.
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3.1.9: Variable Oxidation States (HL):
Explain how the small energy difference between 4s and 3d orbitals allows transition metals to exhibit multiple oxidation states. Compare common oxidation states across the d-block.
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3.1.10: Transition Metal Complexes (HL):
Describe how d-orbital splitting leads to color in transition metal complexes. Explain how factors like ligand identity, metal ion, and charge affect the energy gap and observed color.