Greater Electron Affinity- He of F??

[Turkelton]

One of the trends is that Electron Affinity increase from left to right, and down to up on Periodic Table, but I know there are exceptions.

Which of these atoms has the greatest electron affinity?

A.) He
B.) F
C.) Br
D.) As

Is the answer A or B? I know He is a noble gas, but it does not have a full octet since there are only 2 electrons, since there is no full octet does He have a greater electron affinity than F?? As always thanks in advance.

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[spyderracing32]

For all intents and purposes He has a full octet. It's the only deviation from the octet rule. Therefore, F has the greatest electron affinity.

 

[Live4Life]

For all intents and purposes He has a full octet. It's the only deviation from the octet rule. Therefore, F has the greatest electron affinity.

F because He doesn't want to gain another electron since its "octet" is already full.

 

[MedicineAHP]

I agree with the posts above, since F is more electronegative(the most electronegative element), it will have a higher electron affinity when compared with the others on that list.

 

[LaCasta]

Yes

Electrons have to go somewhere. He only has a 1s orbital which is full.