The Periodic Table topic check · H1 Chemistry 8873

Learning objectives

• recognise variation in the electronic configurations across a Period and down a Group
• describe and explain qualitatively the general trends and variations in atomic radius, ionic radius, first ionisation energy and electronegativity: — across a Period in terms of shielding and nuclear charge
• describe and explain qualitatively the general trends and variations in atomic radius, ionic radius, first ionisation energy and electronegativity: — down a Group in terms of increasing number of electron shells, shielding and nuclear charge
• interpret the variation in melting point and in electrical conductivity across a Period in terms of structure and bonding in the elements (metallic, giant molecular, or simple molecular)
• describe and explain the trend in volatility of the Group 17 elements in terms of instantaneous dipole- induced dipole attraction Trends and variations in chemical properties For elements in the third period (sodium to chlorine), candidates should be able to:
• — state and explain the variation in the highest oxidation number of the elements in oxides (for Na2O; MgO; Al 2O3; SiO2; P4O10; SO3) and chlorides (for NaCl; MgCl 2; AlCl 3; SiCl 4; PCl 5)
• — state and explain the variation in bonding in oxides and chlorides in terms of electronegativity (with the exception of AlCl 3)
• — describe the reactions of the oxides with water (for Na2O; MgO; Al 2O3; SiO2; P4O10; SO3)
• — describe and explain the acid/base behaviour of oxides (for Na2O; MgO; Al 2O3; SiO2; P4O10; SO3) and hydroxides (for NaOH; Mg(OH)2; Al (OH)3), including, where relevant, amphoteric behaviour in reaction with sodium hydroxide (only) and acids
• — describe and explain the reactions of the chlorides with water (for NaCl; MgCl 2; AlCl 3; SiCl 4; PCl 5)
• — suggest the types of structure and bonding present in the oxides and chlorides from observations of their chemical and physical properties For elements in Group 1 (lithium to caesium) and Group 17 (chlorine to iodine), candidates should be able to:
• describe and explain the relative reactivity of elements of: — Group 1 as reducing agents in terms of ease of loss of electrons
• describe and explain the relative reactivity of elements of: — Group 17 as oxidising agents in terms of ease of gain of electrons
• describe and explain the trend in thermal stability of Group 17 hydrides in terms of bond energies In addition, candidates should be able to:
• predict the characteristic properties of an element in a given Group by using knowledge of chemical periodicity
• deduce the nature, possible position in the Periodic Table, and identity of unknown elements from given information of physical and chemical properties