Calcium chloride, or CaCl2, is composed of two Cl- anions ionically bound to a central calcium atom. Calcium has a 2+ charge, and the two chlorine ions each have a 1- charge. Forming ionic bonds with calcium, the chlorine ions achieve full valence electron shells and satisfy the octet rule.
Calcium chloride is a salt of calcium and chlorine and behaves as a typical ionic halide. CaCl2 has a linear molecular geometry, and the chlorine-calcium-chlorine bond angle is 180 degrees. The central calcium atom has two p orbitals that are empty. According to Boise State University, this makes calcium chloride an excellent drying agent since the non-bonding electron pairs of water can attach to these sites.