Correct order of 3^{rd} Ionisation energy of | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(A) The $3^{rd}$ ionisation energy involves the removal of an electron from the $M^{2+}$ ion. The electronic configurations of the $M^{2+}$ ions for $

Vedclass · Accepted Answer

$O > N > C > B$

Vedclass · Answer

(A) The $3^{rd}$ ionisation energy involves the removal of an electron from the $M^{2+}$ ion. The electronic configurations of the $M^{2+}$ ions for $B, C, N,$ and $O$ are:$B^{2+} (Z=5): 1s^2 2s^1$$C^{2+} (Z=6): 1s^2 2s^2$$N^{2+} (Z=7): 1s^2 2s^2 2p^1$$O^{2+} (Z=8): 1s^2 2s^2 2p^2$Comparing these,$C^{2+}$ has a stable fully filled $2s^2$ subshell,which makes its $3^{rd}$ ionisation energy significantly higher than expected.$N^{2+}$ and $O^{2+}$ have higher effective nuclear charge than $B^{2+}$ and $C^{2+}$.The actual order is $N > O > C > B$ is incorrect due to the stability of the $2s^2$ configuration in $C^{2+}$.Correct order is $N > O > C > B$ is wrong; the correct sequence is $O > N > C > B$ based on effective nuclear charge,but considering the stability of $C^{2+}$,the order is $N > O > C > B$ is incorrect. The correct order is $O > N > C > B$.

Correct order of $3^{rd}$ Ionisation energy of $B, C, N$ and $O$ will be

Similar Questions

The electronic configuration with the highest ionization enthalpy is

The first four ionization energy values of an element are $191$,$578$,$872$ and $5962 \ kcal$. The number of valence electrons in the element is

Observe the following statements.
Statement $(A)$: In general,the ionisation potential value decreases on moving down in the group.
Statement $(B)$: The $1$st ionisation potential of sodium is greater than that of potassium.
Correct answer is:

The ionization potential of sodium is $5.48 \ eV$. The $I.P.$ of potassium is ............. $eV$

The values of $\Delta _iH_1, \Delta _iH_2, \Delta _iH_3$,and $\Delta _iH_4$ for an atom are $7.5 \ eV, 25.6 \ eV, 48.6 \ eV$,and $170.6 \ eV$ respectively. Determine the electronic configuration of the atom.

Vedclass Test Series

Exam Paper Generator

Online Exam Module