Across
- 2. an electrically neutral atomic particle in the atomic nucleus
- 4. a vertical column in the periodic table; also known as the family of elements
- 9. any member of a set of atoms of the same element whose nuclei contain the same number of protons but different number of neutrons
- 10. a count of the number of protons in the atomic nucleus
Down
- 1. a positively charged subatomic particle in the atomic nucleus
- 3. any material that is made up of only one type of atom
- 5. a horizontal row on the periodic table
- 6. the dense, positively charged center of every atom
- 7. mass of the elements atoms; sum of the protons and neutrons
- 8. a small, discrete packet of light energy