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| a table illustrating the periodic system, in which the chemical elements, formerly arranged in the order of their atomic weights and now according to their atomic numbers, are shown in related groups. |
| periodic table n. Chemistry A tabular arrangement of the elements according to their atomic numbers so that elements with similar properties are in the same column. |
periodic table n.
A tabular arrangement of the elements according to their atomic numbers so that elements with similar chemical properties are in the same column.
Periodic Table
(click for larger image in new window) A table in which the chemical elements are arranged in order of increasing atomic number. Elements with similar properties are arranged in the same column (called a group), and elements with the same number of electron shells are arranged in the same row (called a period). |