Rank the following elements in order of increasing ionization energy: Sr, He, Si, F
A)Sr

Question

Rank the following elements in order of increasing ionization energy: Sr, He, Si, F
A)Sr < Si < He < F
B)F < Si <He < Sr
C)Sr < Si <F < He
D)Si < F <He < Sr
E)He < F < Sr < Si

Quizplus · Accepted Answer

Ionization energy generally increases across a period (from left to right) and decreases down a group (from top to bottom) in the periodic table. Therefore, among the given elements, strontium (Sr) being an alkaline earth metal will have the lowest ionization energy. Silicon (Si) comes next as it is to the left of fluorine (F) in the same period. Fluorine (F), being a halogen, has a higher ionization energy than both Sr and Si due to its high electronegativity and smaller size. Helium (He), being a noble gas with a completely filled valence shell, has the highest ionization energy among the given elements.

Rank the Following Elements in Order of Increasing Ionization Energy