Across
- 2. A substance at the start of a chemical reaction
- 3. Balancing equations ensures the number of these is the same on both sides
- 4. The centre of an atom that contains protons and neutrons
- 7. The number written in front of a chemical formula when balancing
- 8. A type of radiation made of helium nuclei
- 9. A positively charged particle in the nucleus
Down
- 1. decay The process of unstable atoms giving off energy
- 5. A negatively charged particle in an atom
- 6. A neutral particle found in the nucleus
- 7. The total mass of reactants equals the total mass of products (Law of ______ of mass)