Classes of metals products with soft bases, which are bases with covalent bonds. The IUPAC Gold Book provides a more general definition of a class (a) metal ion, as "A metal ion that combines preferentially with ligands containing ligating atoms that are the lightest of their Periodic Group", and a class (b) metal as one that combines preferentially with ligands containing ligating atoms other than the lightest of their Periodic Group. Classes of metals Class A metals are metals that form hard acids. Hard acids are acids with relatively ionic bonds. These metals, such as iron, aluminium, titanium, sodium, calcium and the lanthanides,
Element of Crime – in English for the first few albums and then in German. The band's name is borrowed from the title of the movie "The Element of Crime" by Lars von Trier. Element of Crime Element of Crime is a German rock band that plays melancholic chanson, pop and rock music with guitar, bass guitar, drums and voice/trumpet. The band was founded in 1985 by Sven Regener who subsequently became known as the author of the books "Herr Lehmann" (2001) (English title "Berlin Blues"), "Neue Vahr Süd" (2004) and "Der kleine Bruder" (2008) and as the screenplay writer of the film