The periodic table shows all of the elements arranged in order of increasing atomic number. Mendeleev (among others) first noticed that certain element characteristics or properties tended to repeat in specific intervals. The idea of 'periodic repetition of properties' lead to the table being known as the periodic table of the elements.
Understandings The periodic table is arranged into four blocks associated with the four sublevels- s, p, d, and f. The periodic table consists of groups (vertical columns) and periods (horizontal rows). The period number (n) is the outer energy level that is occupied by electrons. The number of the principal energy level and the number of the valence electrons in an atom can be deduced from its position on the periodic table. The periodic table shows the positions of metals, non-metals and metalloids. Applications and skills Deduction of the electron configuration of an atom from the element's position on the periodic table, and vice versa. |
In Chapter 5.1