Write down uses of lanthanoids and its compounds.

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Answer

→ Use of the lanthanoids is for the production of alloy steels for plates and pipes.
→ A well known alloy is mischmetal which consists of a lanthanoid metal (~95%) and iron (~5%) and traces of S, C, Ca and Al.
→ A good deal of mischmetal is used in Mg-based alloy to produce bullets, shell and lighter flint.
→ Mixed oxides of lanthanoids are employed as catalysts in petroleum cracking.
→ Some individual Ln oxides are used as phosphors in television screens and similar fluorescing surfaces.

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