Question
Question: The order of electron gain enthalpy (magnitude) of O, S and Se is :...
The order of electron gain enthalpy (magnitude) of O, S and Se is :
A
O > S > Se
B
S > Se > O
C
Se > S > O
D
S > O > Se
Answer
S > Se > O
Explanation
Solution
O has exceptionally smaller value of electron affinity (minimum in family) due to smaller atomic size than sulphur (weaker electron-electron repulsion in larger 3p-subshell).