Understanding the scientific rationale behind Chlorine's position in the periodic table:
Belongs to Group 17 (Halogens) because it possesses 7 valence electrons (3s² 3p⁵).
Belongs to Period 3 because its valence electrons fill the n=3 shell.
Belongs to the p-block because its differentiating electron occupies a 3p orbital.
Classified as a reactive nonmetal due to its high electronegativity (3.16) and strong halogen chemical reactivity.
Hover or tap any shell orbit ring to inspect electron counts and 2n² capacities.
Educational Note: This Niels Bohr planetary model visually illustrates principal quantum energy shells ($n=1, 2, 3\dots$) and electron counts. In modern quantum mechanics (Schrödinger model), electrons do not orbit in fixed circular planetary tracks, but exist as 3D probability clouds (orbitals: $s, p, d, f$) governed by the Heisenberg uncertainty principle.
Neutral ground state configuration. Valence electrons: 7.
Abundant as chloride ions (Cl⁻) in ocean brine (1.9% by mass) and rock salt deposits (halite / NaCl).
From Greek 'chloros' meaning pale green or yellow-green
Extremely toxic and suffocating gas that attacks moist lung tissues to form hydrochloric acid, causing pulmonary edema.