Chapter 5. The Periodic Table. 5-1 Organizing the Elements. What does the word “ periodic ” mean? Periodic : recurring at regular intervals Periodic table – is an arrangement of elements in columns based on a set of properties that repeat from row to row. Mendeleev 1869.
The Periodic Table
3. What happens to the composition of matter during a physical change? Does it change or remain the same?
2. Is flammability a physical property or a chemical property?
4. What does the atomic number of an element represent?
5. Isotopes of element have different numbers of
6. True or False : Electrons in atoms occupy orbitals in energy levels