Across
- 4. has an atomic number and can't be broken down
- 6. the symbol for diatomic hydrogen
- 9. made up of two or more elements
- 10. part of a nucleus with no electric charge
- 13. the middle of an atom
- 14. in H2O the 2 is a
- 15. reactants turn into this during a reaction
- 17. a negatively charged part of an atom
Down
- 1. abbreviations for chemical elements
- 2. enables the formation of molecules
- 3. electrons can be free or
- 5. the symbol for oxygen
- 6. the symbol for water
- 7. a table showing the chemical elements
- 8. a group of atoms
- 11. part of a nucleus with a positive electric charge
- 12. the basic building block of chemistry
- 16. something that changes during a reaction