What you’ll learn10 learning objectivesChoose one objective for a focused lesson, or study the complete topic.1.3.0Scope note• In 1.3 each atom or ion described will be in the ground state. Only the elements hydrogen to krypton will be assessed.Syllabus objective1.3.1Terms• Know terms:: shells, sub-shells and orbitals; principal quantum number (n); ground state, limited to electronic configurationSyllabus objective1.3.2Number of orbitals making up s, p and d• Describe the number of orbitals making up s, p and d sub-shells, and the number of electrons that can fill s, p and d sub-shellsSyllabus objective1.3.3Order of increasing energy of the sub-shells• Describe the order of increasing energy of the sub-shells within the first three shells and the 4s and 4p sub-shellsSyllabus objective1.3.4Electronic configurations to include• Describe the electronic configurations to include the number of electrons in each shell, sub-shell and orbitalSyllabus objective1.3.5Electronic configurations• Explain the electronic configurations in terms of energy of the electrons and inter-electron repulsionSyllabus objective1.3.6Determine the electronic configuration• Determine the electronic configuration of atoms and ions given the atomic/proton number and charge, using either of the following conventions: e.g. for Fe: 1s22s22p63s23p63d64s2 (full electronic configuration) or [Ar] 3d64s2 (shorthand electronic configuration)Syllabus objective1.3.7The electrons in boxes notation• Understand and use the electrons in boxes notation e.g. for Fe: [Ar]Syllabus objective1.3.8And sketch the shapes of s and p orbitals• Describe and sketch the shapes of s and p orbitalsSyllabus objective1.3.9Free radical as a species with one or more• Describe a free radical as a species with one or more unpaired electronsSyllabus objective