Praseodymium neodymium samarium

It surprises most people to learn that several of the so-called rare earth elements are not actually that rare compared to much more familiar elements. Neodymium, praseodymium, samarium, gadolinium, dysprosium, erbium, and ytterbium are all more abundant than more familiar elements like bromine, uranium, or tin. Europium, holmium, terbium, lutetium, and thulium are more abundant than iodine, silver, or mercury. Yet few people have even heard of most of the rare earths. The reason is that rare earths tend not to concentrate in large ore deposits in the way that better known metals do. Historically there have been fewer profits to be made from mining rare earth elements, and there have been fewer applications developed for them in industry. 

Parameter Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium... 

These include the following 14 elements cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmi-um, erbium, thulium, ytterbium, and lutetium. 

After the brilliant researches of Bunsen and Kirchhoff had paved the way, other new elements were soon revealed by the spectroscope. Among these may be mentioned thallium, indium, gallium, helium, ytterbium, holmium, thulium, samarium, neodymium, praseodymium, and lutetium. 

B. Evans, Assistant Chemist. Rare-Earth Information Center. Energy itnd Mineral Resources Research Institute. Iowa Slate University. Ames. I,A. http //www.cxternal.ameslab.gov/. Cerium Dysprosium Erbium Europium Gadolinium Holmium Lanthanum Lutetium Neodymium Rare-Earth Elements and Metals Praseodymium Samarium Scandium Terbium Thulium Ytterbium and Yttrium Daniel F. Farkas, Oregon State University. Corvallis. OR. http // oregonstate.edu/. Food Processing... 

Eecent work by L. M. Dermis2 and his co-workers has shown that electrolysis may be of considerable value in effecting a complete or partial separation of the oxides of the rare earth metals. Prom a neutral solution of the nitrates of neodymium, praseodymium, lanthanum, and samarium, nearly all the lanthanum is deposited as hydroxide in the last fractions discharged on the cathode. The hydroxides are deposited fractionally in order of their basicity, and the deposition is not dependent upon the... 

Rare earth nitrates can be prepared using nitric acid to react with a corresponding oxide, hydroxide, carbonate or metal. These nitrates dissolve easily in polar solvents such as water, alcohols, esters or nitriles. They are unstable to heat as the decomposition temperature for the nitrates of scandium, yttrium, lanthanum, cerium, praseodymium, neodymium, and samarium are 510,480, 780,450, 505, 830, and 750 °C, respectively. 

Chromates of the Rare Earth Metals.—A series of isomorphous yellow chromates, sparingly soluble in water, and of general formula E2 (Cr04)3.8H30, where R=Lanthanum, Praseodymium, Neodymium, or Samarium, has been prepared. ... 

Praseodymium Neodymium... Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium... 

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