| Definition | Term |
| The ease and speed with which an element reacts with other substances | |
| The modern periodic table is arranged in order of increasing ______. | |
| True or false: Most metals are not good conductors of heat and electricity. | |
| Every atom of an element has the same number of _____. | |
| Negatively charged particles in an atom | |
| True or false: The number of protons always stays the same as the number of electrons in an atom. | |
| Describes how shiny a metal is | |
| Number of electrons that can be held in the second shell (spell out number | |
| The most reactive type of metal | |
| Scientist who discovered electrons | |
| Positively charged particles in an atom | |
| Columns in the periodic table | |
| Atoms with the same number of protons and different numbers of neutrons | |
| Scientist who thought that electrons were found in specific orbits around the nucleus | |
| True or false: Most metals are solid at room temperature. | |
| Scientist who discovered that the atom had a positively charged nucleus | |
| A material that can be hammered or rolled into flat sheets or other shapes is said to be _____ | |
| Unit used to measure the mass of an atom (abbreviation) | |
| Particles that move around in the cloud-like region of the atom | |