Question

question 5 (1 point) which of the following elements is predicted to have the lowest ionization energy? p n o i

Explanation:

Step1: Recall ionization - energy trend

Ionization energy decreases down a group and increases across a period in the periodic table.

Step2: Locate elements in periodic table

P (phosphorus) is in Group 15 and Period 3, N (nitrogen) is in Group 15 and Period 2, O (oxygen) is in Group 16 and Period 2, I (iodine) is in Group 17 and Period 5.

Step3: Compare positions

Since Iodine (I) is the furthest down among these elements, it has the largest atomic radius and the out - most electron is the least tightly held. So it has the lowest ionization energy.

Answer:

I