Across
- 4. the chemicals used at the start of the reaction
- 5. the solid produced when two chemicals react
- 9. an arrangement of all known elements in order of their size and structure
- 10. smallest particle of matter
- 11. pure substances containing only one type of atom
- 13. mass is always the same at the start and end of a reaction
- 16. number of protons in an atom
- 20. two or more different atoms joined together
- 22. when two smaller chemicals join in a reaction
- 23. new chemicals are made
- 24. two or more molecules or compounds
- 25. neutral particles in an atom found in the nucleus
Down
- 1. when chemicals swap partners in a reaction
- 2. the study of matter and how it behaves
- 3. shows what chemicals are at the start and end of a reaction
- 4. how a reaction happens
- 6. new chemical formed, not easily reversed
- 7. what a chemical looks like and how it behaves
- 8. when a chemical breaks apart into two or more chemicals in a reaction
- 12. the chemicals made by the equation
- 14. an atom or molecule with a net electric charge due to the loss or gain of one or more electrons
- 15. positive particles in an atom found in the nucleus
- 17. number of protons plus neutrons in an atom
- 18. a aection with oxygen (burning)
- 19. two or more atoms joined together
- 21. the process of gaining knowledge by observation and experiment