Across
- 1. cows and rice add …. Gas to the atmosphere
- 5. a gas ….. is used to collect measure gas in an experiment
- 9. chemicals that go into a chemical reaction
- 10. makes a squeaky pop when put next to a lit 🔥 splint
- 11. a chemical reaction where the outside environment gets cold afterwards
- 13. when you add two clear solutions together a solid salt is formed
- 17. millions of years ago ……….. caused an atmosphere with mostly carbon dioxide
- 19. in fractional distillation of hydrocarbons, the hydrocarbons with the ….. boiling points condense and form liquids at the bottom of the fractioning tank where it is hottest
- 20. bigger molecules have stronger ……. between them and need higher temperatures to break them (like Velcro)
- 21. form covalent bonds sharing an electron between two of the same element
- 24. discovered electrons and made the plum pudding model
- 25. grew on earth and photosynthesised which added oxygen to the atmosphere
- 27. a solid and a base => a salt and ……….
Down
- 2. biological catalysts
- 3. way of measuring reaction rate when a solid is formed in the reaction
- 4. carbon dioxide turns …. Water cloudy
- 6. ……….. dioxide causes acid rain
- 7. discovered atoms have a central positively charged nucleus which makes up most of the atoms mass
- 8. method of breaking big hydrocarbons into smaller ones
- 12. alkaline metals become …… reactive as you go down the periodic table
- 14. ignites a glowing splint
- 15. discovered electron shells
- 16. a hydrocarbon used as fuel in many forms of transport
- 18. number of electrons halogens have on outside shell
- 22. soot particles are very harmful for people with …..
- 23. this substances put together for a particular use eg paint alloys
- 25. how a line on a graph measuring reaction rate over time looks when a reaction stops happening
- 26. a ….. gradient shows a faster reaction rate