Question

Which of the following has highest electron gain enthalpy?

• A. $O$
• B. $S$
• C. $Se$
• D. $Te$

Answer 1

The correct option is B $S$

$\text{Electron gain enthalpy - It is detined as the ammount}$

$\begin{array}{c}\text{of energy released when an electron is added to}\\ \text{an isolated gaseous atom.}\end{array}$

$\begin{array}{c}\text{In periodic table Left to Right increases and}\\ \text{Top to bottom decreses}\end{array}$

$\text{size :}O<S<Se<Te$

$\begin{array}{c}\text{Size of oxygen is small as compare to}S\text{,}\\ \text{so, it is not e- added so easily, hence}\\ \text{S have highest electron gain enthalpy.}\end{array}$