Question

Sulfur has a lower ionization energy than chlorine because 1. the effective nuclear charge of sulfur is less than that of chlorine. 2. sulfur has a greater ionization energy than chlorine. 3. the outer orbitals of sulfur are located farther from the nucleus than the outer orbitals of chlorine. 4. the effective nuclear charge of sulfur is greater than that of chlorine. 5. sulfur elevates one of its p electrons to a d orbital, thus making it easier to remove the electron.

Answer 1

Answer: the effective nuclear charge of sulfur is less than that of chlorine

Explanation:

Ionization Energy can be defined as the energy needed for the complete removal of valence electron.

Ionization Energy decreases steadily down the group because of the outer electrons becomes progressively separated from the nucleus, hence they are less tightly held.

Also, Ionization Energy increases from left to right across the period i.e formation of a cation becomes more difficult owing to increase in nuclear charge.

Therefore, the effective nuclear charge of sulfur is less than that of chlorine because Chlorine have a greater ionization energy.