CH 101 Chapter Notes - Chapter 4: Pauli Exclusion Principle, Effective Nuclear Charge, Valence Electron
Document Summary
Section 4. 1: aluminum: low density atoms result in low-density metal. Aluminum atoms have a very low density: 2. 70 g/cm3. This causes the density of aluminum metals to also be very low. The density of elements tends to increase as you move down a column in the periodic table. Periodic property- a property that is generally predictable based on an element"s position within the periodic table: structure determines properties. The arrangement of elements in the periodic table reflects how electrons fill quantum-mechanical orbitals. Section 4. 2: finding patterns: the periodic law and the periodic table. First attempt to organize elements was by johann dobereiner, who grouped them into triads triad- group of 3 elements with similar properties. Next attempt was by john newlands, who organized them into octaves: the properties of every eighth element were similar. When the elements are arranged in order of increasing mass, certain sets of properties recur periodically.