| A | B |
|---|
| Mendeleev | Chemist, forrunner of the periodic table |
| The Periodic Law | When elements are arranged in order of increasing atomic number, their physical and chemical properties show a periodic pattern |
| periods | horizontal rows in the periodic table |
| metalloids | elements along the zigzag line |
| valence electrons | What similar properties do elements in the same group have? |
| periodic trend | Many properties of elements change in a predictable way as you move through the periodic table |
| joule | unit of measure required to move electrons |
| potassium atom | Which is largest? sodium atom, sodium ion with 1+ charge or potassium atom |
| electron affinity | the energy change that occurs when it gains an extra electron |
| electronegativity | What is an atoms ability to attract electrons in a chemical bond? |
