Question

what is the decreasing order of electron gain enthalpies of halogens​

Answer 1

$\bf\large\underline\red{Answer:-}$

➤ Hence its electron gain enthalpy is less negative than Cl. But, on going down from Cl to I, due to decrease in electronegativity, the electron gain enthalpy also decreases. So, the order of increase in elctron gain enthalpy of halogens is:- I<Br<F<Cl.

❒_____________________________

Answer 2

ANSWER IS Cl < F < Br < I

Explanation:

MARK THE ANSWER AS THE BRAINLIEST ANSWER

The increasing order of electronic enthalpy is given below:

Cl < F < Br < I

In periodic table, down in the group means from "top to bottom", the electron gain enthalpy becomes "less negative". This is because of increasing in size from F to I.

"Electron gain enthalpy" is termed as the energy change when we add "electron to the valence shell" to a gaseous atom which is neutral.

In case of halogens, fluorine shows "less negative" electron gain enthalpy when compared to chlorine because of small size and 2s22p5 configuration .