You can go online at Costco.com and apply for a Costco Membership there by adding it to your shopping cart if you are shopping for the first time. Your membership card will be mailed to you within 7-10 days but you can actually shop at the online store immediately.
The three most common chlorine-containing substances used in water treatment are chlorine gas, sodium hypochlorite, and calcium hypochlorite.
Chlorine Cl 17 35 Halogen used as a bleaching agent, component of common. table salt, used as a disinfectant and water purifier. Bromine Br 35 80 Halogen, which is a brownish liquid at room temperature, used. in medicines, dyes, and photography.