Question
Question: Among halogens, the correct order of amount of energy released in electron gain (electron gain entha...
Among halogens, the correct order of amount of energy released in electron gain (electron gain enthalpy) is.
A
F > Cl > Br > I
B
F < Cl < Br < I
C
F < Cl > Br > I
D
F < Cl < Br > I
Answer
F < Cl > Br > I
Explanation
Solution
: Electron gain enthalpy becomes less negative on moving down a group due to increase in atomic size. However, the electron gain enthalpy of F is less negative than that of Cl due to electron – electron repulsion in small sized F atom. Thus, the correct order is:
F < Cl > Br >I
ΔegH(kJmol−1) -328 -349 - 325 -295