Dec 10, 2025 · periodic table, in chemistry, the organized array of all the chemical elements in order of increasing atomic number —i.e., the total number of protons in the atomic nucleus.

Dec 10, 2025 · During the development of modern atomic physics and the theory of quantum mechanics, a precise and detailed understanding was obtained of the electronic structure of …

The periodic table is a tabular array of the chemical elements organized by atomic number, from the element with the lowest atomic number, hydrogen, to the element with the highest atomic …

Dec 10, 2025 · The periodic table of the elements contains all of the chemical elements that have been discovered or made; they are arranged, in the order of their atomic numbers, in seven …

This is an interactive periodic table of the elements showing their atomic weights, atomic numbers, electron configurations, and state at room temperature.

Dec 10, 2025 · With the exception of hydrogen and mercury, the gaseous and liquid elements occur in the right-hand part of the periodic table, the region associated with the nonmetallic …

periodic table, Organized array of all the chemical elements in approximately increasing order of their atomic weight.

The periodic table arranges the elements in rows and columns. In the rows, the elements are placed in order of their atomic number. The columns form groups of elements that have similar …

Holmium, chemical element, a rare-earth metal of the lanthanide series of the periodic table. Holmium is a moderately hard, silvery white metal that is relatively stable in air. It is a very …

Nov 19, 2025 · Mercury, chemical element, liquid metal of Group 12 of the periodic table. Mercury is the only elemental metal that is liquid at room temperature. Mercury is silvery white and …