Periodic table

3. The first name of the Russian scientist who was credited with this creation
4. The mass of an isotope of an element in atomic mass units
7. The type of elements that are in the last group
9. Ability for something to be shining
10. All elements in this series can be found on Earth except, 1 radioactive element
13. They partially conduct electricity, and are used in computer chip industries.
14. The name you call the element.
16. When in their pure form most of them are ductile, and are good conductors of heat and electricity
19. Tells you how many protons are in the nucleus
20. The definition you use when you look at the rows(from left to right)

1. All elements in these series are radioactive and some you can’t find on Earth.
2. Ability to be hammered down thin
5. The other name the periodic table is known for, also the last name of Dmitri ^
6. The 1 or 2 letter(s) that is used to be written in compounds that the element is in.
8. They are brittle, and poor conductors of heat and electricity.
11. Ability to be drawn out into wire or threads
12. A airlike fluid substance that expands to any open space
15. It can fill up the exact shape of a container
17. The definition you use when you look at columns(from top to bottom)
18. It will maintain their shape when held