Based on position in the periodic table and electron configuration, arrange these elements in order of decreasing Ei1. Rank the elements from highest to lowest ionization energy. To rank items as equivalent, overlap them.
S, As, Ga, Se, K, Rb

Ionization energy is the energy required to remove an electron from an atom of a chemical element. Ionization energy depends on the atomic radius of an element.

Ionization energy and the periodic table.

Ionization energy increase across the period from left to right and decreases along the group from top to bottom on the periodic table.

Ranking the elements from highest to lowest ionization energy, We have:

S - Sulphur

S - SulphurK - Potassium

S - SulphurK - PotassiumRb - Rubidium

S - SulphurK - PotassiumRb - RubidiumSe - Selenium

S - SulphurK - PotassiumRb - RubidiumSe - SeleniumAs - Arsenic

S - SulphurK - PotassiumRb - RubidiumSe - SeleniumAs - ArsenicGa - Gallium

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Ionization energy is a measure of how strongly an atom holds onto its electrons. A higher ionization energy indicates th...

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Rb<K<Ga<As<Se<S

Explanation:

We must remember that first ionization energy decreases down the group and increases across the period.

First ionization energy decreases down the group because of the addition of more shells which increases the distance between the nucleus and the outermost electron. Hence, Rb has a lower ionization energy that K.

Across the period, increase in the size of the nuclear charge causes the pull of the nucleus on the outermost electrons to increase thereby increasing the ionization energy. Hence ionization energy increases across the period. For this reason, the ionization energy of Ga<As<Se as shown.