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 ...

This lesson utilizes an adaptation of the board game Periodic: A Game of the Elements to help students better understand both general periodic trends and the law of conservation of energy. This ...

At the middle of the 19th century, 63 chemical elements were known to science. Before Mendeleev’s discovery, attempts at arranging them in some logical way were made by Johann Doebereiner (1829), ...

Standard atomic weights, those numbers emblazoned under the elements on the periodic table, were once thought of as unchanging constants of nature. But researchers have tweaked the atomic weights of ...

One hundred fifty years after Russian chemist Dmitri Mendeleev published his system for neatly arranging the elements, the periodic table it gave birth to hangs in every chemistry classroom in the ...

Every field of science has its favorite anniversary. For physics, it’s Newton’s Principia of 1687, the book that introduced the laws of motion and gravity. Biology celebrates Darwin’s On the Origin of ...

The iconic chart of elements has served chemistry well for 150 years. But it’s not the only option out there, and scientists are pushing its limits. By Siobhan Roberts When Sir Martyn Poliakoff, a ...