Description

any of us relate swimming pools, and even fun summer time, when thinking about chlorine.  Calcium Hypochlorite is the most popular powder sanitizer among private swimming pool owners.  It is an inorganic compound with formula Ca(ClO)2.  This compound is relatively stable and has greater available chlorine than sodium hypochlorite (liquid bleach). It is a white solid, (although commercial samples appear yellow) that is added in granular or tablet form to pool water to kill germs that can make swimmers sick.  It strongly smells of chlorine, owing to its slow decomposition in moist air.  It is not highly soluble in hard water, and is more preferably used in soft to medium-hard water.  It has two forms: dry (anhydrous); and hydrated (hydrous). 

Generally the commercial substances are sold with a purity of 65% to 73% chlorine concentration, mixed with other chemicals present, such as calcium chloride and calcium carbonate, resulting from the manufacturing process.  As you can see having a relatively high concentration of chlorine, other than liquid bleach, it tends to be the most cost effective of chlorine sanitizers.  As a swimming pool chemical, it is blended with other chemicals less often than other forms of chlorine, due to dangerous reactions with some common pool chemicals. In solution, calcium hypochlorite could be used as a general purpose sanitizer, but due to calcium residue, sodium hypochlorite (bleach) is usually preferred.