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Statement-1 : The third ionisation entha...

Statement-1 : The third ionisation enthalpy of La, Gd and Lu are abnormally low.
Statement-2 : Empty, half-filled and completelt filled orbitals of f-level are extra stable.

A

Statement-1 is True, Statement-2 is True, Statement-2 is a correct explanation for Statement-1.

B

Statement-1 is True, Statement-2 is True, Statement-2 is not a correct explanation for Statement-1.

C

Statement-1 is True, Statement-2 is false

D

Statement-1 is False and Statement-2 is True.

Text Solution

Verified by Experts

The correct Answer is:
A
`La^(3+) rarr 4f^(0), Gd^(3+) rarr 4f^(7), Lu^(3+) rarr 4f^(14)`
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