Across
- 7. what year was the first periodic table created in
- 8. who discovered a set of patterns that applies to all elements?
- 9. all elements are considered what?
- 10. according to what was the first table arranged
Down
- 1. tells us the amount of protons/electrons
- 2. word for a regular or repeated pattern
- 3. a letter or abbreviation to describe an element
- 4. what were most of the elements discovered by 1869?
- 5. How many elements were discovered by 1869?
- 6. mass the average mass of all isotopes of that element