Joel Achenbach writes about science and politics for The Washington Post's National desk. He has been a staff writer for The Post since 1990. He started the newsroom’s first online column, Rough ...

Take the numbers in order from the code sheet and match them to the atomic symbols (one- or two-letter abbreviations) on the filled-in periodic table. Do that, and you’ll get a sentence (after ...

When you enter the laboratory, you will find a table on the wall in the shape of the periodic table. However, instead of the element, there are numbers in certain squares of the table. While it is ...

The discovery of Mendeleev’s periodic table The first version of Mendeleev’s periodic table, published in 1869, was reportedly completed in just one day. Historians have pieced together what ...

So, if it’s 13:03:23, that would light up aluminum in blue, lithium in green, and vanadium in red. The periodic table was designed in Adobe Illustrator and UV printed on a sheet of translucent ...