Question

question 9. arrange the following elements from lowest to highest ionization energy: bromine (br), iodine (i), chlorine (cl), fluorine (f) answer: bromine (br) iodine (i) chlorine (cl) fluorine (f)

Explanation:

Step1: Recall ionization energy trend

Ionization energy generally increases across a period and decreases down a group in the periodic table. These elements (Br, I, Cl, F) are in Group 17 (halogens). Down the group, atomic size increases, so ionization energy decreases (since outer electrons are farther from the nucleus, easier to remove).

Step2: Determine group position

The order of these elements from top to bottom (increasing atomic number and size) in Group 17 is: F, Cl, Br, I. So the order from lowest to highest ionization energy (since lower down the group, lower ionization energy) is I (lowest), then Br, then Cl, then F (highest).

Answer:

Iodine (I) < Bromine (Br) < Chlorine (Cl) < Fluorine (F)