Chlorides, particularly sodium chloride (NaCl) and calcium chloride (CaCl 2), play significant roles in the chemistry of cement and concrete. Often introduced through deicing salts and seawater exposure or as admixtures to accelerate curing, chlorides interact with the hydration process of cement. They can promote the rapid development of early strength in concrete but also lead to corrosion issues in steel reinforcement. The presence of chlorides in concrete is a critical factor, especially in terms of durability and longevity, as they facilitate the electrochemical reactions that lead to steel corrosion within the concrete matrix.