| What is an atom? | smallest particle of an element that maintains the properties of that element |
| What is atomic mass? | average mass number of all atoms of an element (from particles in the nucleus) |
| What does the atomic number represent? | the number of protons in the nucleus of an atom; used to determine an element's position in the Periodic Table |
| What is a chemical property? | a characteristic of a substance that describes how it combines with other substances to form new ones |
| What is an electrical charge? | a property of a subatomic particle; positive (protons), negative (electrons), or neutral (neutrons) |
| What is an electron? | a negatively charged particle in the electron cloud surrounding the atomic nucleus |
| What is an electron cloud? | the negatively charged space containing electrons that surrounds the atomic nucleus |
| What is an element? | a pure substance that cannot be broken down chemically into simpler substances |
| What are groups (families)? | the vertical columns on the Periodic Table |
| What is a mass number? | total number of protons and neutrons in a specific atom |
