In comparison to boron, berylium has :

Question:

In comparison to boron, berylium has :

  1. lesser nuclear charge and lesser first ionisation enthalpy.

  2. greater nuclear charge and lesser first ionisation enthalpy.

  3. greater nulear charge and greater first ionisation enthalpy.

  4.  lesser nuclear charge and greater first ionisation enthalpy.


Correct Option: , 4

Solution:

Nuclear charge : $\mathrm{B}>\mathrm{Be}$

$\mathrm{Be}=1 s^{2} 2 s^{2}$                (more stable)

$\mathrm{~B}=1 s^{2} 2 s^{2} 2 p^{1}$

$\therefore$ Ionisation energy of Be is greater than B due to $n s^{2}$ outer electronic configuration.

Leave a comment