Question

Question 11.23 Explain why is there a phenomenal decrease in ionisation enthalpy from carbon to silicon?

Class XI The p-Block Elements Page 324

Answer 1

         As we move from carbon to silicon atomic size increases.e.g., the distance between the outermost electron and nucleus increases. Thus, this electron experience very small attraction from the nucleus and hence, easy to remove . since, the size of Si - atom id larger, the outermost electron experience lesser attraction and hence, its ionization Enthalpy {energy required to remove an electron from an isolated gaseous atom is known as ionization enthalpy.} is smaller.

Answer 2

Explanation:

As we move from carbon to silicon atomic size increases, i.e., the distance between the outermost electron and nucleus increases. Thus, this electron experience very small attraction from the nucleus and hence, easy to remove. Since, the size of Si atom is larger, the outer electron experience lesser attraction and hence, its ionisation enthalpy (energy required to remove an electron) is smaller.