Q9 of 26 Page 1

What are alloys? Name an important alloy which contains some of the lanthanoid metals. Mention its important use.

An alloy is a blend of metals prepared by mixing the components. Alloys may be homogeneous solid solutions in which the atoms of one metal are distributed randomly among the atoms of the other. Such alloys are formed by atoms with metallic radii that are within about 15 percent of each other. Because of similar radii and other characteristics of transition metals, alloys are readily formed by these metals. The alloys so formed are hard and have often high melting points.


An important alloy which contains some of the lanthanoid metals is Mischmetall. It consists of approximately 95% Ln, 5% Fe and traces of C, Si, Ca, Al and Mg.


Mg based mischmetall is used in production of bullets, shells and lighter flint.


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