No abstract

In Abbildung 3 ist die druckprogrammierte Trennung der Cs-bis C14-n-Paraffine an der gleichen stationaren Phase gezeigt. Die gestrichelte Linie beschreibt den -von C1 bis c 8 praktisch exponentiell ansteigenden -Druckabfall an der Saule als Funktion der Zeit.

beyond the already inquired but also compelled it to radically revise its basic assumptions. The discovery of radioactive elements that disintegrate spontaneously, and the discovery of cathode rays and of their corpuscular nature posed peremptorily the problem of the structure of the atom. The old notion of the unchangeability and indivisibility of the atomand with it of the elementshad finally died. The gradual recognition of the mysterious language of atomic spectra as a code on the subtler structure of matter, culminating i n Bohr's concept of atomic structure in 1913, marked the beginning of a new era, and of a new understanding of all that was contained in the age-old question on the elements and their compounds. Modern atomic physics has given us the tools for a deeper understanding of the hitherto enigmatic order of the elements in the periodic system, and of their existence and reactivity. "Atomic shell" "atomic nucleus", and electron "shell-structure"furnished the first important concepts for the explanation of what was traditionally called the "properties" and the "qualities" of the elements. Finally, the Pauli principle also provided a solution to the enigma of the periodic law, which MendelCeff had already sought to resolve by ever renewed and unsuccessful attempts. The wonderful ground-plan of the periodic system could now be reconstructed, and one could at last rationalize the hitherto hidden order of the chemical elements.