Calcium Chloride is a salt of calcium and chloride. It behaves as a typical ionic halide, and is solid at room temperature. Calcium chloride is a commonly used reagent in biochemistry. It plays important roles in many biological processes, including signal transduction, muscle contraction, and maintenance of cell membrane and cell wall stability. Calcium chloride is used in the preparation and transformation of competent E. coli and in the transfection of eukaryotic cells with either plasmid DNA or high molecular weight genomic DNA. Has been used in the stabilization and two dimensional crystallization of the NADH-ubiquinone oxidoreductase (complex I) from Escherichia coli. It is also used as a desiccant, coagulant in rubber manufacturing and as an accelerator in the concrete industry.