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 ...

The atomic number of tellurium is 52 and the atomic number of iodine is 53, so these elements are in the correct order in the modern periodic table.

It wasn’t until 1913, six years after Mendeleev’s death that the final piece of the puzzle fell into place. The periodic table was arranged by atomic mass, and this nearly always gives the same order ...