Question Bank [2022] — Chemistry STD 12 Science — Question
Maharashtra BoardEnglish MediumSTD 12 ScienceChemistryQuestion Bank [2022]3 Marks
Question
What are rare earth elements?
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Answer
Although, historically, lanthanoids are termed as rare earth elements, they are fairly abundant in earth’s crust. e.g. Thulium is found more in abundance than silver $(4.5 \times 10^{–5}$ vs $0.79 \times 10–5$ percent by mass).
The names rare earth elements was coined because of difficulty in extracting them economically in pure form from other lanthanoids having similar chemical properties. Now, due to newer separation methods like ion exchange resins, the separation of these elements has become easier and more economical.
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