Which following pairs of atoms, have a lower electron affinity? a) Ca,K b) I,F c) Li, Ra. I seriously don't know anything about electron affinity all ik that it can buy another element
Answers
It is the amount of energy released when an atom in gaseous state accepts an electron to form an anion.
▶Its dependence :-
✳A small atom takes up electrons readily rather than a large atom so atomic size decreases electron affinity increases.
✳Nuclear charge increases so the tendency of accepting a electron increases so electron affinity increases.
◼Across a period
Atomic radius decreases so electron affinity increases and nuclear charge increases so electron affinity increases.
Overall, electron affinity increases.
◼Across a group
Atomic radius increases so electron affinity should decrease.
Nuclear charge increases so electron affinity should increase.
Since atomic radii dominates over nuclear charge so overall it decreases.
◼For K and Ca
The lies in the group 1 and 2 and in period 4 so they have least electron affinity.
◼For I and F
They lies in group 17 and in period 2 and 5 , so as they lies in end of period so they have most electron affinity.
◼For Li and Ra
They lies in group 1 and 2 and in period 2 and 7 ,so Li will have a low affinity but Ra will have the least reactivity among all given elements in the question.