SO2 and Cl2 are both effective bleaching agents but operate through different mechanisms. Chlorine bleaching relies on oxidation, requiring nascent oxygen, while sulfur dioxide acts as a reducing agent, producing sulfonic acid and sulfite ions. The bleaching effect of chlorine is permanent and can damage delicate fibers, making it suitable for robust materials like cotton and jute. In contrast, SO2 provides a milder, temporary bleaching action, ideal for sensitive fabrics such as silk and wool. Understanding these differences is crucial for selecting the appropriate bleaching agent for specific materials.