# Transition metals and their compounds are widely used as catalysts in industry. Explain why transition metals are able to act as catalysts, and state TWO other properties of transition metals that make them useful in everyday applications.

> Edexcel A-Level Chemistry (9CH0) — 15.1 Transition metal chemistry · Explain · 5 marks

> Transition metals such as iron, copper and nickel are found in the d-block of the periodic table. They have a number of characteristic properties that distinguish them from other metals.

## Mark scheme (5 marks)

1. Transition metals can have variable oxidation states (accept: variable valency)
2. This allows them to accept and donate electrons during a reaction, enabling them to form temporary bonds with reactant molecules / providing an alternative reaction pathway
3. The catalyst is not used up / remains chemically unchanged at the end of the reaction
4. One correct property stated — e.g. high melting point / high density / good conductor of electricity / high tensile strength
5. A second correct and different property from the list above

## Key terms

- [transition metals](https://www.gradenine.co.uk/glossary/transition-metals)
- [catalyst](https://www.gradenine.co.uk/glossary/catalyst)

## Related

- [Revision notes for Edexcel A-Level Chemistry (9CH0)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

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Source: [GradeNine](https://www.gradenine.co.uk/q/transition-metals-and-their-compounds-are-3aae672a) · Published by Druglandscape Ltd.