Iron and copper are both transition metals. Describe three properties that iron and copper share which are typical of transition metals, and for each property explain how it differs from the properties of a Group 1 metal such as sodium.
Written & reviewed by James Millett — Biology (Imperial College London), PGCE Science (University of Cambridge).
Transition metals occupy the central block of the periodic table. They include familiar metals such as iron, copper, nickel and chromium.
Model answer (5 marks)
1. High melting point – iron and copper melt at 1538 °C and 1085 °C respectively, far higher than sodium’s 97.8 °C.
2. Variable oxidation states – Fe²⁺ and Fe³⁺; Cu⁺ and Cu²⁺, whereas sodium only forms Na⁺.
3. Colourful compounds – copper(II) salts are blue/green, iron(III) salts orange/brown; sodium salts are colourless.
Each property is typical of transition metals and contrasts with the low melting point, single +1 oxidation state and colourless nature of Group 1 metals such as sodium.
2. Variable oxidation states – Fe²⁺ and Fe³⁺; Cu⁺ and Cu²⁺, whereas sodium only forms Na⁺.
3. Colourful compounds – copper(II) salts are blue/green, iron(III) salts orange/brown; sodium salts are colourless.
Each property is typical of transition metals and contrasts with the low melting point, single +1 oxidation state and colourless nature of Group 1 metals such as sodium.
Examiner tips
- Use the exact terms ‘high melting point’, ‘variable oxidation states’, ‘colourful compounds’.
- Show the numerical melting points for iron and copper and compare with sodium’s 97.8 °C.
- State the specific oxidation states (Fe²⁺/Fe³⁺, Cu⁺/Cu²⁺) and contrast with Na⁺ only.
Common mistakes
- Saying ‘high density’ instead of ‘high melting point’.
- Confusing sodium’s colourless compounds with coloured transition‑metal compounds.
- Not specifying the exact oxidation states of iron and copper.
Mark scheme (5 marks)
- Transition metals have high melting points / high densities / are hard and strong (any one physical property correctly stated)
- This physical property is much greater than that of sodium / Group 1 metals, which have low melting points / low densities / are soft (correct contrast stated)
- Transition metals can form ions with different / variable oxidation states (e.g. Fe²⁺ and Fe³⁺, or Cu⁺ and Cu²⁺)
- Sodium only forms one type of ion (Na⁺) / Group 1 metals always form 1+ ions, so they do not show variable oxidation states
- Transition metal compounds are often coloured (e.g. copper compounds are blue/green, iron(III) compounds are orange/brown) whereas sodium compounds are generally white / colourless
Key terms in this question
Related
- All Edexcel A-Level Chemistry (9CH0) revision notes →
- How to answer a "Describe" question →
- Decode the mark scheme abbreviations →
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