Question

To which of the following atom, the attachment of electron is most difficult?

• A. Radium
• B. Nitrogen
• C. Oxygen
• D. Radon

Answer 1

The correct option is D Radon

(a) Randon is anoble has or inertgas, it has stable filles shell configuration. $\left(Xe\right)4f^{11}5d^{10}6s^{2}6p^6$

(b) Nitrogen is $Gr.{15}^{th}$ element, it has half filled $2p$ orbital.
$\left(He\right)2s^{2}2p^3$

(c) Oxygen is $Br.{16}^{th}$ element. $\left(He\right)2s^{2}2p^4$

(d) Radium is $Gr{2}^{nd}$ element. $\left(Rn\right)7s^2$
The attachment of electron is most difficult for radon.
So, the correct answer is A.