CHEM 1201 Lecture Notes - Atomic Number, Covalent Bond, Atomic Radius
Document Summary
As a consequence of the well ordering in the periodic table, properties of elements vary periodically. Atomic size varies consistently through the periodic table. As we move down a group (column), the atoms become larger. As we move across a period (row), atoms become smaller. 4 - : as the principle quantum number, n, as we move across the periodic table (size), increases (i. e. , we move down a group, column), the distance of the outermost electron from the nucleus becomes larger. , the number of core electrons = (i. e. noble gas configuration) remains constant. However, the nuclear charge/size increases (becomes more positive). Therefore, there is an increased attraction between the (+) nucleus and the outermost (-) electrons. This attraction causes the atomic radius to decrease (left to right). Effective nuclear charge experienced by an electron on a many- electron atom.
