This how it works covers Why Transition Metals Form Coloured Compounds and Act as Catalysts within Transition Metals (HT) for GCSE Chemistry. Revise Transition Metals (HT) in Atomic Structure for GCSE Chemistry with 20 exam-style questions and 21 flashcards. Use this page as part of a wider topic revision path rather than treating it as an isolated fact. It is section 3 of 12 in this topic. Use this how it works to connect the idea to the wider topic before moving on to questions and flashcards.
⚙️ Why Transition Metals Form Coloured Compounds and Act as Catalysts
Unlike the main group metals (Groups 1 and 2), transition metals have two remarkable properties. First, transition metal ions absorb some wavelengths of visible light, reflecting back the remaining wavelengths as colour. Different transition metals absorb different wavelengths, which is why copper compounds are blue, iron(III) compounds are orange-brown, and potassium permanganate is purple. Second, transition metals can form ions with variable charge (e.g., Fe²⁺ and Fe³⁺). This ability to switch between ion charges makes them excellent catalysts: they can temporarily accept electrons from one reactant and then donate them to another, speeding up reactions without being permanently changed. This is why iron catalyses the Haber process and platinum catalyses reactions in catalytic converters.
Practice questions for Transition Metals (HT)
Where in the periodic table are the transition metals located?
Explain why copper is a useful metal for electrical wiring.