Sodium hydroxide is a chemical compound having the formula NaOH. It’s also referred to as sodium hydroxide structure. It’s white in colour and consists of sodium cations Na+ and hydroxide anions OH−. Other names of sodium hydroxide are Ascarite, White caustic, Sodium hydrate.  It appears as a white, waxy, opaque crystal and has no odour. It’s soluble in glycerol, negligible in ammonia, insoluble in ether and slowly soluble in propanediol.

What is Sodium Hydroxide?
Sodium hydroxide is also known as caustic soda as it is made from a highly caustic base and alkali that decomposes proteins at ordinary ambient temperatures and should cause severe chemical burns. It’s highly soluble in water, and readily absorbs moisture and CO2 from the air. It forms a series of hydrates like NaOH.nH2O. Sodium hydroxide is employed in many industries: within the manufacture of pulp and paper, textiles, beverage, soaps and detergents, and as a drain cleaner.
Sodium hydroxide structure can form several hydrates NaOH.nH2O, which end in a posh solubility diagram. The known hydrates and therefore the approximate ranges of temperature and concentration (mass per cent of NaOH) of their saturated water solutions. Sodium hydroxide also reacts with acidic oxides, like sulphur dioxide. Such reactions are often wont to “scrub” harmful acidic gases (like SO2  and H2S) produced within the burning of coal and thus prevent their release into the atmosphere.

Production
For industry purpose, sodium hydroxide structure is produced as a 50% solution by variations of the electrolytic chloralkali process. Chlorine gas is an added product during this process. Solid caustic soda is obtained from this solution by the evaporation of water. Solid NaOH is most ordinarily sold as flakes, prills, and cast blocks. Historically, NaOH has been produced by treating washing soda with lime during a metathesis reaction which takes advantage of the very fact that NaOH is soluble, while carbonate isn’t. It is in use while purifying the bauxite ore from which aluminium metal is extracted. This process is the Bayer process.