question_answer

In the following, the element with the highest ionisation energy is:

A)  \[\text{ }\!\![\!\!\text{ Ne }\!\!]\!\!\text{  }3{{s}^{2}}3{{p}^{1}}\]

B)  \[\text{ }\!\![\!\!\text{ Ne }\!\!]\!\!\text{  }3{{s}^{2}}3{{p}^{3}}\]

C)  \[\text{ }\!\![\!\!\text{ Ne }\!\!]\!\!\text{  }3{{s}^{2}}3{{p}^{2}}\]

D)  \[\text{ }\!\![\!\!\text{ Ne }\!\!]\!\!\text{  }3{{s}^{2}}3{{p}^{4}}\]

Correct Answer: B

Solution :

Elements having half-filled or fully filled orbitals are more stable. Hence, much energy is required to remove an electron from the outermost orbit. So, \[\text{ }\!\![\!\!\text{ Ne }\!\!]\!\!\text{  }3{{s}^{2}}3{{p}^{3}}\]has highest ionisation energy.