This study explores the effects of pulsed laser irradiation on a chlorine monolayer (ML) chemisorbed on Si(100), focusing on modifications induced by surface melting, etching, and cleaning. The investigation employs time-of-flight mass spectrometry (TOF) for desorbed molecules, Auger electron spectroscopy (AES) for surface modifications, and Cl depth profiling via secondary ion mass spectrometry (SIMS). Experimental results reveal evidence of Cl diffusion into the bulk silicon during surface melting and significant segregation of Cl during recrystallization. The fraction of Cl monolayer initially adsorbed on Si is independently measured by TOF and SIMS, showing branching ratios for reactive desorption, subsurface incorporation, and deeper layer diffusion. The study finds that Cl diffusion into the bulk during laser melting effectively limits surface Cl concentration to 0.40 ± 0.03 Si ML per laser pulse. Additionally, strong segregation of Cl at the surface during recrystallization results in minimal Cl contamination in the bulk, making Si an effective material for laser cleaning applications.