Anions such as chloride (Cl −), sulfate (SO 4 2−), and carbonate (CO 3 2−) play significant roles in the chemistry of cement and concrete, particularly under severe environmental conditions. These anions often originate from external sources such as deicing salts, sea water, or industrial emissions and can profoundly influence the durability and integrity of concrete structures. Understanding the interaction of these anions with cementitious materials is critical for designing concrete that can withstand harsh environments, including those with high moisture, saline conditions, and exposure to sulfates.