JEE Main 2021 — D And F Block Elements Question with Solution
From: JEE Main 2021 (Online) 16th March Morning Shift
Question
Given below are two statement : one is labelled as Assertion A and the other is labelled as Reason R :
Assertion A : Size of Bk3+ ion is less than Np3+ ion.
Reason R : The above is a consequence of the lanthanoid contraction.
In the light of the above statements, choose the correct answer from the options given below :
Assertion A : Size of Bk3+ ion is less than Np3+ ion.
Reason R : The above is a consequence of the lanthanoid contraction.
In the light of the above statements, choose the correct answer from the options given below :
Choose an option
Show full solutionCorrect option: C
Correct answer
CA is true but R is false
Step-by-step explanation
Size of Bk3+ is 98 pm
Size of Np3+ is 101 pm
So size of Np3+ is more than Bk3+ ion.
there is a gradual decrease in the size of M3+ ions across the series. This may be referred to as the actinoid contraction.
Size of Np3+ is 101 pm
So size of Np3+ is more than Bk3+ ion.
there is a gradual decrease in the size of M3+ ions across the series. This may be referred to as the actinoid contraction.
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