Answer:
"c" is the element with the most negative electron affinity.
Explanation:
We can obtain the following information from the electron configuration:
Period: Is the level in which the differential electron is in.
Group: Is the sum of all electrons in the last level.
Knowing their ubication in the periodic table, we can classify them as metals, nonmetals or noble gases.
a. 5s² P: 5 G: IIA (2) Metal
b. 5s²5p² P: 5 G: 2 + 2 = IVA (14) Nonmetal
c. 5s²5p⁵ P: 5 G: 2 + 5 = VIIA (17) Nonmetal
d. 5s²5p⁶ P: 5 G: 2 + 6 = VIIIA (18) Noble gas
Noble metals have a low tendency to gain electrons so their electron affinity is neglectable. For elements in the same period, the electron affinity gets more negative from left to right. Therefore, "c" is the element with the most negative electron affinity.