Periodic Table Gallery

An exciting time for chemistry

Two new elements, flerovium Fl and livermoreium Lv have been approved for entry in the Periodic Table of the Elements! They were formerly known by blander names—ununquadium and ununhexium. In honor of the event, I assembled a gallery of periodic tables, but let me tell you more about the table first.

The chemical elements are arranged from top to bottom, in order of lowest to highest atomic number. (Atomic number is the same as the number of protons.) There are 118 elements. 98 are naturally occurring, and 14 occur naturally in decay chains of those 98, up to and including californium. The remaining six elements are lab synthesized.

Periodic Tattoo

Why is it periodic?

Table rows are “periods” and table columns are “groups.” Some groups have specific names, e.g. the noble gases, occupying the last column on the right. Some rows do too, such as the lanthanides and actinides on the bottom two rows.

The table is also periodic because its inventor, Dmitri Mendeleev, intended for it to be updated periodically, as new elements are found. So Mendeleev’s design had a dual use: for describing how the elements relate to each other, as well as for inferring the properties of new and not yet found elements.

One scientific concept to rebuild civilization

The children’s Periodic Table on the U.S. EIA website has the basics. It links to Los Alamos National Lab’s (LANL) Periodic Table.

Actinides at LANL

Here is a great quote from a recent LANL news story by David Hobart, Actinide Analytical Chemistry, History of the periodic table…and my history with it:

As the legendary physicist Richard Feynman put it, “If some universal catastrophe was to engulf the world and humankind could retain only one scientific concept to rebuild civilization, what would it be? The chemist’s answer is almost invariably the Periodic Table of the Elements.“

Graphene trading card one day maybe

I was inspired by the story of this year’s Nobel Laureates in Physics, particularly Professor A. Geim. He was an Ig-Noble prize winner a mere ten years ago.

Graphene and Scotch tape for the win

Fast forward to mid-October 2010. Geim and his research colleague K. Novoselov won the Nobel Prize for their discoveries with graphene, a carbon-based material with remarkable properties. Graphene is stretchable into a one atom-thick sheet, is exceptionally strong, conducts electricity and heat better than copper, yet is chemically inert. Graphene was first synthesized from graphite in the early 1980s, but scientists soon gave up on it. It seemed impossible to get it into a useful form, as it would just roll back up on itself into a nanotube or other curved surface.

Then, there was this one AMAZING trick that Geim (now Professor Sir Andre Geim, Regius Professor at The University of Manchester), and Novoselov did with graphene and Scotch tape:

Researchers had concluded that …freestanding graphene could not be isolated. But in 2004, Geim and Novoselov, who was a postdoc at the time, worked out a surprisingly simple method for exfoliating little chips of graphite by folding adhesive tape against the crystals and peeling apart the tape repeatedly.

In doing so, Geim and Novoselov demonstrated that not only could atom-thick sheets of graphite, i.e. graphene, be isolated, but also discovered that graphene was highly stable at room temperature.

Non-quantum chemistry

Put aside thoughts of cigarettes. Note the style, humor, and backdrop of the image below. It is whimsical, in the spirit that I attribute to Professor Geim as he did his Ig Nobel presentation, years before.

Chemistry trading card: Many Florence flasks!

Image credit: Churchman’s Cigarettes, via the Chemical Heritage Foundation on Flickr

Science Trading Card, (Imperial Tobacco Co.), early 20th century:

Investigation of the natural world by observation, quantification, repetition, and comparison extends right up until the early 20th century, when this trading card was made. Then scientists began exploring matter at the atomic level. . .

The trading card scene is also evocative of the more experimental aspect of Geim’s and Novoselev’s work. I think that had become quite uncommon by the late 1990s. The atomic age had been around for a long time by then.

I was surprised at the German Lindau Nobel Laureate Meeting’s informal tone in their backgrounder on Professor Sir Andre Geim and his discovery:

Graphene is a plane of carbon atoms arranged into what looks like chicken wire. It can also be viewed as a gigantic molecule consisting of zillions of benzene rings.

That’s exactly what this one atom-thick swatch of graphene looks like, as viewed with a scanning tunneling microscope!

Graphene is a lattice of carbon atoms

Lindau’s description of Geim’s past work with mini batrachians is casual too.

In 1997, while exploring diamagnetism of water, Geim demonstrated that most things are magnetic enough to be levitated by strong magnets… including a live frog. For this, he and Sir Michael Berry were awarded the satirical Ig Nobel Prize in 2000. The pair accepted the award for being able to “keep a sense of humor and self-deprecation”.