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AN earth scientist has rejigged the periodic table to make chemistry simpler
to teach to students.

There have been many attempts to redesign the periodic table since Dmitri
Mendeleev drew it up in 1871. But Bruce Railsback from the University of Georgia
says he is the first to create a table that breaks with tradition and shows the
ions of each element rather than just the elements themselves.

“I got tired of breaking my arms trying to explain the periodic table to
earth scientists,” he says, criss-crossing his hands in the air and pointing to
different bits of a traditional table. Railsback has still ordered the elements
according to the number of protons they have. But he has added contour lines to
show charge density, helping to explain which ions react with which.

“Geochemists just want an intuitive sense of what’s going on with the
elements,” says Albert Galy from the University of Cambridge. “I imagine this
would be good for undergraduates.”

Railsback has listed some elements more than once. He explains that sulphur,
for example, shows up in three different spots—one for sulphide, which is
found in minerals, one for sulphite, and one for sulphate, which is found in sea
salt, for instance.

He has also included symbols to show which ions are nutrients, and which are
common in soil or water. And the size of an element’s symbol reflects how much
of it is found in the Earth’s crust.