Periodic Table

4. The important characteristics of an element in the periodic table are its atomic symbol, atomic number and mass number.
6. The first element of the periodic table as its atomic number is one.
7. The number of electrons will equal the number of protons.
8. A positively charged particle that resides within the atomic nucleus.
12. The vertical columns on the periodic table are called groups or families because of their similar chemical behavior.
13. The periodic table of chemical elements, often called the periodic table, organizes all discovered chemical elements in rows
16. A chemical element with the symbol (N) and atomic number 7.
17. A chemical element with symbol ( CA ) and atomic number 20.
18. A substance that contains only one type of atom.
19. A one or two letter symbol that represents the element.

1. Atoms are composed of protons, neutrons, and electrons, which are composed of the basic building blocks of matter.
2. A chemical element with the symbol ( C ) and atomic number.
3. A particle of matter that uniquely defines a chemical element.
4. A substance made up of two or more different chemical elements combined in a fixed ratio.
5. Table: organizes all discovered chemical elements in rows and columns according to increasing atomic numbers.
9. chemical element of the alkali metal group of the periodic table.
10. The method by which elements are grouped on the basis of their characteristics.
11. The chemical elements are what the periodic table classifies and organizes.
14. A chemical element with the symbol (HE) and atomic number 2.
15. A transition metal, grouped with cadmium and mercury.