Question

What is effective nuclear charge and the periphery of nitrogen atom when an extra electron is added in the formation of an anion?

• A. $1.20$
• B. $2.45$
• C. $3.55$
• D. $5.95$

Answer 1

The correct option is C $3.55$

When an extra electron is added in nitrogen atom, added electron will be screened by five electrons in second orbit $\left(2s^{2}2p^3\right)$ and two electrons in first orbit $\left(1s^2\right)$.

Now screening constant, $\sigma =5\times 0.35$ in $nthorbit+2\times 0.85$ in $(n-1)th$ orbit

$=1.75+1.70=3.45$

$\therefore$ Effective nuclear charge $=7-3.45=3.55$.