Chemical element same atomic number, or number of protons. Nuclear scientists, however, define a pure element as one that consists of only one stable isotope. For example, a copper wire is 99.99% chemically pure if 99.99% of its atoms are copper, with 29 protons each. However it is not isotopically pure since ordinary copper consists of two stable isotopes, 69% Cu and 31% Cu, with different numbers of neutrons. However, a pure gold ingot would be both chemically and isotopically pure, since ordinary gold consists only of one isotope, Au. Atoms of chemically pure elements may bond to each other chemically in
¡Cu-Cut! the team of editors and illustrators continued their work at Catalan children's magazine "En Patufet". On the occasion of the first centennial of the closure of the magazine, the Barcelona City Historical Archive ("Arxiu Històric de la Ciutat de Barcelona") staged an exhibition and published a catalogue based on the once famous magazine. The exhibition was commissioned by Catalan cartoonist Jaume Capdevila ("Kap") and produced with the "Associació Tantatinta". ¡Cu-Cut! ¡Cu-cut! was a Catalan illustrated satirical magazine, written in Catalan. Published in Barcelona between 1902 and 1912, it followed the political line marked by Francesc Cambó's Lliga Regionalista. ¡Cu-cut!, named