| A | B |
|---|
| electron cloud | the space around the nucleus where electrons travel |
| electrons | particles with a negative charge |
| protons | located within the nucleus with a positive charge |
| represents most of the atoms mass | nucleus |
| atomic number | equal to the number of protons and electrons |
| energy levels | the different areas for an electron in an atom |
| first energy level | can hold a maximum of 2 electrons |
| second energy level | can hold a maximum of 8 electrons |
| third energy level | can hold a maximum of 18 electrons |
| fourth energy level | can hold a maximum of 32 electrons |
| Noble Gases | uses include producing neon lights, and filaments is lightbulbs |
| electron dot diagram | the symbol for the element surrounded by as many dots as there are electrons in its outer energy level. |
| chemcial bond | the force that holds two atoms together. |
| ion | an atom that is no longer neutral because it has lost or gained an electron |
| ionic bond | a chemical bond |
| compound | pure substance containing two or more elements that a chemically bonded |
| metallic bond | metal atoms share or pool their electrons |
| covalent bond | chemical bond that forms when atoms share electrons |
| molecule | the neutral particle formed when atoms share electrons. |
| polar bond | a bond in which electrons are shared unevenly |
