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The periodic table of chemical elements, often called the periodic table, organizes all discovered chemical elements in rows (called periods) and columns (called groups) according to increasing atomic ...
You may use table navigation commands for the screen reader of your choice. The Periodic Table of Elements. Each entry contains the atomic number, chemical symbol, and atomic mass to two decimal ...
There are 118 elements in the periodic table, each with a unique symbol and atomic number. Symbol: A one or two-letter abbreviation used to represent the element. Atomic number: The number of ...
But how many of these elements do you know? Test your knowledge and compete with other Live Science readers to see who can ...