Within each pair of elements F & Cl, S & Se, and Li & Na, respectively, the elements that release more energy upon and electron gain are :
Solution
Electron affinity of second period p-block
element is less than third period p-block element
due to small size of second period p-block element.
<br><br>$\therefore$ Electron affinity order : F $<$ Cl
<br><br>Down the group electron affinity decreases due
to size increases.
<br><br>$\therefore$ Electron affinity E.A. order : S $>$ Se
<br><br>Li $>$ Na
About this question
Subject: Chemistry · Chapter: Periodic Table and Periodicity · Topic: Periodic Trends
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