Today, the periodic table is organized by atomic number, which is the number of protons in the nucleus. But they didn’t know about protons then, so they organized everything by atomic weight.

The periodic table is part of the bedrock of chemistry education. Students use it to look up values like an element’s atomic mass, and it serves as a visual reference for the trends in physical ...

Wothers finds many such twists in the stories hidden behind the squares of the periodic table. Antimony (element No. 51) is a lustrous mineral; four thousand years ago, people carved vases out of ...

The periodic table captures a subtle pattern that runs through the chemical elements , the fundamental building blocks of everything around us: from the aluminium in bike frames to the xenon gas ...

The period table song, featuring 118 elements. This is a corrected version of a story originally published Jan. 28, 2019. The earlier story said the Periodic Table was published in 1859 instead of ...

It’s not every day an element gets added to the periodic table. The last time it happened was 2016, when four new elements became official. For these elements, reaching the table was an epic ...

The periodic table shows all the atoms that everything in the known universe is made from. It’s kind of like the alphabet in which only 26 letters, in different combinations, make up many thousands of ...

A new study lays the groundwork to expand the periodic table with a search for element 120, to be made by slamming electrically charged titanium atoms, or ions, into a californium target.

Give each student a Periodic Table of Energy Levels activity sheet. This table contains energy level models for the first 20 elements. The electrons are included only for the atoms at the beginning ...

A new version of the periodic table of elements has predicted hundreds of highly charged ions that could be used to create the next generation of optical atomic clocks. The periodic table, first ...

Since the turn of the century, six new chemical elements have been discovered and subsequently added to the periodic table of elements, the very icon of chemistry. These new elements have high ...

The periodic table of elements is a landmark categorization developed in 1869 by the Russian chemist and inventor Dmitri Mendeleev. It arranges all natural and synthetic elements by their atomic ...