Why is the ionization energy of Cl lower than F, but higher than that of S? (4.7)

Verified step by step guidance

1. Understand the concept of ionization energy: Ionization energy is the energy required to remove an electron from an atom in the gaseous state. It generally increases across a period and decreases down a group in the periodic table.
2. Consider the position of Cl and F in the periodic table: Both chlorine (Cl) and fluorine (F) are in Group 17 (halogens), but F is above Cl in the periodic table.
3. Analyze the trend in ionization energy within a group: As you move down a group, the ionization energy decreases because the outer electrons are farther from the nucleus and are more shielded by inner electrons, making them easier to remove.
4. Compare Cl and F: Since F is above Cl, F has a higher ionization energy than Cl because its electrons are closer to the nucleus and less shielded, making them harder to remove.
5. Compare Cl and S: Chlorine (Cl) is to the right of sulfur (S) in the same period. Ionization energy increases across a period due to increasing nuclear charge, so Cl has a higher ionization energy than S.

Key Concepts

Ionization Energy

Ionization energy is the energy required to remove an electron from an atom in its gaseous state. It reflects how strongly an atom holds onto its electrons; higher ionization energy indicates a stronger attraction. Trends in ionization energy can be influenced by atomic size, nuclear charge, and electron shielding.

Periodic Trends

Periodic trends refer to predictable patterns in elemental properties across the periodic table. Ionization energy generally increases across a period (left to right) due to increasing nuclear charge and decreases down a group (top to bottom) because of increased atomic size and electron shielding. Understanding these trends helps explain variations in ionization energy among elements.

Electron Configuration

Electron configuration describes the distribution of electrons in an atom's orbitals. The arrangement of electrons affects an atom's reactivity and ionization energy. For chlorine (Cl), fluorine (F), and sulfur (S), their electron configurations reveal how many electrons are in their outer shells, influencing their ionization energies and the stability of their electron arrangements.