Across
- 3. each horizontal row of the periodic table
- 5. the tiny central core of an atom and is composed of protons and neutrons
- 6. the smallest particle of an element that retains its identity in a chemical reaction
- 7. an arrangement of elements in which the elements are separated into groups based on a set of repeating properties
- 10. subatomic particles with no charge but with a mass nearly equal to that of a proton
Down
- 1. each vertical column of the periodic table
- 2. the total number of protons and neutrons in an atom
- 4. an atom that has the same number of protons but a different number of neutrons
- 8. a negatively charged subatomic particle
- 9. positively charged subatomic particles