28.1 Physical and chemical properties of first-row transition elementsSyllabus2028–2030Topic28.1LevelA2
What you’ll learn6 learning objectivesChoose one objective for a focused lesson, or study the complete topic.28.1.1Transition element• Define a transition element as a d-block element which forms one or more stable ions with incomplete d orbitalsSyllabus objective28.1.2Sketch the shape of a 3dxy orbital and 3dz²• Sketch the shape of a 3dxy orbital and 3dz² orbitalSyllabus objective28.1.3Transition elements have properties• Understand: transition elements have the following properties:: (a) they have variable oxidation states; (b) they behave as catalysts; (c) they form complex ions; (d) they form coloured compoundsSyllabus objective28.1.4Why transition elements have variable• Explain why transition elements have variable oxidation states in terms of the similarity in energy of the 3d and the 4s sub-shellsSyllabus objective28.1.5Why transition elements behave as catalysts• Explain why transition elements behave as catalysts in terms of having more than one stable oxidation state, and vacant d orbitals that are energetically accessible and can form dative bonds with ligandsSyllabus objective28.1.6Why transition elements form complex ions• Explain why transition elements form complex ions in terms of vacant d orbitals that are energetically accessibleSyllabus objective