Question

The first ionisation energy of siliconand sulphur are lower than that of phosphorous ​

Answer 1

Ionisation energy of Silicon and sulphur compared with Phosphorous

Explanation:

Ionisation energy

It is the energy required to remove a electron from outermost shell of an atom .

It depends upon many factors :

• Size of an atom
• Nuclear charge of atom
• Electronic configuration of atom
• Shielding effect  

If we compare the ionization energy of silicon and sulphur with phosphorous then :

It is seen that the ionisation energy of silicon and sulphur are lower as compared to phosphorous because phosphorous is comparatively smaller  in size , therefore its nuclear charge is more and due to this energy required to remove electron is higher .

Whereas  sulphur and silicon are quite big as compared to phosphorous , therefore nuclear charge is comparatively less .Thus , they have lower ionisation energy .