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,
Recycling Rates of Metals report would certainly benefit from greater metals recycling. Among the least-recycled metals are tellurium and gallium, which are used in solar cells, and lithium, which is a key component of the batteries in electric cars. Stocks of these metals are often tied up in old gadgets, such as out-of-date mobile phones, which people often leave in a cupboard and forget about. The report’s authors concluded that appropriate recycling infrastructure should be developed, supported by policy instruments such as research and development, economic incentives and capacity-building activities. Recycling Rates of Metals report Recycling Rates of Metals: A Status Report was the 2nd