Question
Question: Why is the electron gain enthalpy of O or F less than that of S or Cl?...
Why is the electron gain enthalpy of O or F less than that of S or Cl?
A
O and F are more electronegative than S and Cl.
B
When an electron is added to O or F, it goes to a smaller (n = 2 ) level and suffers more repulsion than the electron in S or Cl in larger level (n = 3).
C
Adding an electron to 3p – orbital leads to more repulsion than 2P – orbital.
D
Electron gain enthalpy depends upon the electron affinity of the atom.
Answer
When an electron is added to O or F, it goes to a smaller (n = 2 ) level and suffers more repulsion than the electron in S or Cl in larger level (n = 3).
Explanation
Solution
: there is more repulsion for the incoming electron when the size of atom is smaller.