Across
- 6. two or more substances that are mixed together but are not chemmically bonded
- 10. happens when one chemical substance is transformed into one or more different substances, such as when iron becomes rust.
- 11. mass per unit volume
- 12. Are made of protons, neutrons, electrons
- 13. substance in which two or more different elements are chemically bonded together
- 14. the starting materials in a reaction
Down
- 1. the substances produced in the reaction
- 2. the number of protons and neutrons together in the nucleus of an atom
- 3. the number of electrons surrounding the nucleus of an atom
- 4. an expression of a chemical reaction
- 5. a process in which the structure of atoms or molecules that make up a substance are changed
- 7. a substance composed of a single kind of atom
- 8. shows all known elements in the Universe
- 9. an abbreviation of the element name