Across
- 2. The average mass of all the natural isotopes of an element, found on the periodic table.
- 4. Atoms of the same element with differing numbers of neutrons.
- 5. The sum of protons and neutrons in the nucleus of a single atom.
- 6. Subatomic particle that is in the nucleus and has no charge.
- 10. Subatomic particles that move quickly around the nucleus in discrete orbits and have a negative charge.
Down
- 1. Particles that make up the atom; includes protons, neutrons, and electrons.
- 3. The number of protons in an atom’s nucleus, found on the periodic table
- 7. The small, dense, central region of the atom where protons and neutrons are located.
- 8. Subatomic particle that is in the nucleus and has a positive charge.
- 9. Smallest form of matter that still retains the properties of the element.