Across
- 2. gaseous fuel
- 4. The lowest temperature at which a substance catches fire.
- 8. A combustible substance
- 10. Combustion which gives off heat, light and produces sound.
- 11. Moderate hot zone
- 12. Colour of hottest zone
- 14. The substances which have very low ignition temperature and can easily catch fire with a flame.
- 15. unburnt wax vapours
Down
- 1. Combustion without any apparent cause
- 3. a solid fuel
- 5. number of zones the flame is divided into
- 6. heat and light is produced in sun by the process of
- 7. Substance vapourise during burning forms
- 9. A chemical process in which a substance reacts with oxygen to give off heat
- 13. colour of coolest zone of flame