Which of the following has the most negative electron affinity?
A)H
B)Li
C)Na
D)K
E)Rb

Question

Quizplus · Accepted Answer

The electron affinity of H is the least negative amongst the given options. This is because the effective nuclear charge experienced by the incoming electron in H is the highest, making it more difficult for the electron to be added. The trend for electron affinity generally increases from left to right across a period and decreases from top to bottom in a group. Hence, Li, Na, K, and Rb all have higher electron affinities than H.

Which of the Following Has the Most Negative Electron Affinity