Transition elements
Introduced| English | Meaning |
|---|---|
| transition elements/trænˈsɪʃn ˈelɪmənts/ | transition elements |
| catalysts/ˈkætəlɪsts/ | A substance that increases a reaction rate without being used up overall. |
| variable charges/ˈveərɪəbl ˈtʃɑːdʒɪz/ | variable charges |
The metals in the middle
- The big block of metals in the centre of the table includes iron, copper and gold.
- These are the transition elements 过渡元素, with their own special properties.
Transition element lab
Match transition-metal properties to real examples.
Which are properties of transition metals? (Select all that apply.)
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They are dense, not low-density.
Transition metals are more reactive than Group I metals.
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False. Transition metals are much less reactive than the alkali metals, which is why iron and copper can be used for structures and pipes.
Properties of transition metals
- They are hard, strong, dense, with high melting points.
- They are far less reactive than the Group I metals.
The transition metals form the central block of the periodic table
Many transition metals are useful as:
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E.g. iron catalyses the Haber process.
Unlike most other metals, transition-metal compounds are often ______.
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E.g. blue copper sulfate.
Coloured and catalytic
- Their compounds are often coloured (e.g. blue copper sulfate, green iron compounds).
- Many are useful catalysts 催化剂 (e.g. iron in the Haber process).
Transition metals can form ions with:
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E.g. iron forms Fe²⁺ and Fe³⁺.
Variable charges 可变电荷
- Transition metals can form ions with different charges (e.g. iron as Fe²⁺ or Fe³⁺).
- This is unlike Group I or II metals, which have a single fixed charge.
Transition metals differ from Group I in every way. They are harder, denser, much less reactive, form coloured compounds, and act as catalysts — the opposite of the soft, reactive Group I metals.
You've got it
- transition elements are hard, strong, dense, with high melting points
- they form coloured compounds and act as catalysts
- they have variable charges (e.g. Fe²⁺ and Fe³⁺), unlike Group I/II
Write from variable oxidation states
- Iron can form Fe2+ and Fe3+ compounds.
- Those compounds are coloured. Group I metals form only 1+ ions.
Which transition-metal property is the pair of iron ions?
More than one stable ion charge means variable oxidation states.
What property do Fe2+ and Fe3+ show?
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Two different positive charges are two oxidation states.