Across
- 5. substances that are made of only one type of atom or only one type of molecule
- 8. any change that results in the formation of new chemical substances.
- 9. the positively charged central core of an atom
- 10. with no net electric charge and a mass slightly larger than that of a proton
Down
- 1. the number of protons in the nucleus of an atom
- 2. physical substance in general
- 3. with a positive electric charge of +1e elementary charge and mass slightly less than that of a neutron.
- 4. the mass of an atom
- 6. each of more than one hundred substances that cannot be chemically interconverted or broken down into simpler substances and are primary constituents of matter
- 7. changes affecting the form of a chemical substance, but not its chemical composition.