Sodium hypochlorite

June 30, 2008
Image of Sodium hypochlorite

If you weren't a chemist, you'd know sodium hypochlorite (NaClO) as bleach, or possibly as the "chlorine" you put in your swimming pool or spa. NaClO solution is a convenient way to handle chlorine in an aqueous solution; it is prepared by absorbing chlorine gas in sodium hydroxide solution. Industrially, NaClO solution is produced directly by electrolyzing sodium chloride solution.

MOTW update:
August 9, 2021

Sodium hypochlorite (NaClO) has been widely used for >200 years; but until now, the crystal structure of its pentahydrate (the normal solid form) had not been established. Tomislav Friščić and co-workers at McGill University (Montreal), working at –100 °C because NaClO•5H2O liquefies at ambient temperature, determined the structure of a single crystal, shown. The structure consists of alternating layers of Na+ and ClO ions “glued” together by water molecules.

Sodium hypochlorite structure consists of alternating layers of Na+ and ClO– ions “glued” together by water molecules.
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