CHEM 20A Lecture Notes - Lecture 3: Atomic Number, Periodic Trends
6 Sep 2016
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Document Summary
The size of elements increases as you go down and to the left on the periodic table. Ionization energy increases as you go up and to the right on the periodic table. A triad is a group of three elements in a row, either vertically or horizontally. Vertical triads are a direct consequence of period lengths. Every other triad will not work because of the variation in period length i. e. 2, 8, 8, 18, 18, 32, 32 Many elements have atomic weights that are multiples of the atomic weight of hydrogen all other elements were composed from hydrogen. In the universe, h fused together to form he, he fused together to form be, and so on. The property of elements in periodic table changes with position in table of element as a consequence of atomic numbering. The periodic system is the general concept upon which periodic tables revolve (periodic) table vs, law vs. system.
