Thermochemistry and reactivity of rare earth metals

Reactivity of the rare earth metals towards the different elements is descr ibed. Comments are mainly made on the thermodynamic data relevant to the fo rmation of the binary compounds and to their trends. The different behaviou r of the trivalent rare earths and of europium and ytterbium is underlined. An indication is also given for a few reactions involving more complex rea gents or compounds. Comments are finally made on the use of the reported da ta in the discussion of the preparation and handling methods of the rare ea rth metals and of their alloys.