Across
- 1. number the sum of the protons and the neutrons in the element
- 5. table the elements are arranged by increasing atomic number and by changes in physical and chemical properties
- 6. the vertical columns in the periodic table
- 9. cloud area around the nucleus of an atom where its electrons are most likely found
- 10. small positively charged center of the atom. contains the protons and neutrons
- 11. protons and neutrons are made of even smaller particles called
- 13. dot diagram uses the symbol of the element and dots to represent the electrons in the outer energy level
Down
- 2. atomic mass the weighted-average mass of the mixture of its isotopes
- 3. number the number of protons in the element
- 4. the smallest piece of matter that still retains the properties of the element
- 5. particles with a positive 1 charge
- 7. particles with a negative 1 charge
- 8. atoms of the same element that have different numbers of neutrons. (different mass numbers)
- 10. neutral particles that have 0 charge
- 12. the horizontal rows in the periodic table