Period 1 element Period 1 element A period 1 element is one of the chemical elements in the first row (or period) of the periodic table of the chemical elements. The periodic table is laid out in rows to illustrate periodic (recurring) trends in the chemical behaviour of the elements as their atomic number increases: a new row is begun when chemical behaviour begins to repeat, meaning that elements with similar behaviour fall into the same vertical columns. The first period contains fewer elements than any other row in the table, with only two: hydrogen and helium. This situation can be explained by
The Periodic Table of Science Fiction possibility not normally open to a writer." The print edition was published in 2005, in two signed limited editions: one slipcase hardback edition with a print run of 200, and one hardback edition with a print run of 500 books. In 2009, Swanwick posted the stories on a weblog dedicated to the purpose. The theme of each story in the collection is inspired by the element it is named after. The book also includes an afterword by the author, and a foreword by Theodore Gray who was awarded the IgNobel Prize for Chemistry in 2002. The Periodic Table of Science