Across
- 2. the upper layer of soil
- 5. the ability to do work
- 8. a generic term for non-renewable energy sources
- 9. formed from pre-existing rocks or pieces of once-living organisms
- 10. the process of wearing or being worn by long exposure to the atmosphere
Down
- 1. the changes in which new substance with new chemical properties are formed
- 3. forms when hot, molten rock crystallizes and solidifies
- 4. a recurrent series of events or processes in plants and animals
- 6. a change in matter which does not alter the chemical properties of the matter
- 7. an organised group of related objects or components that form a whole