99 Percentile Qs Bank for JEE MainChemistryd and f Block Elements
Which of the following statements is TRUE?
Options
- ALa ( OH ) 3 is the least basic among hydroxides of lanthanides.
- BZr 4+   and   Hf 4+ possess almost the same ionic radii.
- CThe oxide Ln 2 O 3 reacts with water to form soluble hydroxides.
- DLanthanoids are naturally available.
Correct answer
B. Zr 4+   and   Hf 4+ possess almost the same ionic radii.
Step-by-step solution
Zr   and   Hf both belongs to d - block elements. In d - block elements, the last electron enters into the d - block and due to the poor shielding of f - block elements contraction in the atomic radii as well as ionic radii is observed, therefore both Zr 4+   and   Hf 4+ possess almost the same ionic radii.