A lot vs. Alot: 9 Grammatical Pitfalls
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 |
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).