MCQ
Rare-earth elements are exhibited by
- ✓At. No. $58$ to $71$
- BAt. No. $21 $ to $30$
- CAt. No. $39$ to $ 71$
- DAt. No. $81$ to $91$
✓
Answer
Correct option: A.
At. No. $58$ to $71$
a
(a) Atomic no. $58$ to $71$ are rare earth metals.
(a) Atomic no. $58$ to $71$ are rare earth metals.
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