Sodium Sulfite

By Ellis Charles On Jun 27, 2019

Sodium sulphite or Sodium sulfite is a soluble sodium salt of H₂SO₃(sulfurous acid). The chemical formula of Sodium Sulfite is Na₂SO₃. It is widely used as a preservative for meat, used in the conversion of elemental halogens to hydrohalic acids. It is a byproduct of sulfur dioxide (SO₂).

Properties:

The molecular Weight of Na₂SO₃ is 103.047 g/mol and the exact mass is equal to 102.947 g/mol. The number of hydrogen bond acceptor equals to four whereas the number of hydrogen bond donor equals to zero. Its complexity is 28.4 and has a formal charge of -1. The number of covalently bonded unit is equal to two.

Preparation of Sodium Sulfite

Laboratory level:

In laboratories, sodium sulfite can be prepared by reacting sodium hydroxide (NaOH) solution with sulfur dioxide (SO₂) gas. The reaction is given below:

2 NaOH + SO₂ → Na₂SO₃ + H₂O

Development of SO₂ by adding a few drops of concentrated hydrochloric acid (HCl) designates if sodium hydroxide (NaOH) is gone or turned into aqueous sodium sulfite. The reaction is as follows:

Na₂SO₃ + 2 HCl → 2 NaCl + SO₂ + H₂O

Industry level:

At an industrial level, sodium sulfite is prepared by reacting sulfur dioxide (SO₂) with a solution of sodium carbonate (Na₂CO₃). The beginning combination produces sodium bisulfite (NaHSO₃), which is further converted to sulfite by the reaction of sodium carbonate or sodium hydroxide.

The reaction is as follows:

SO₂ + Na₂CO₃ → Na₂SO₃ + CO₂

Applications of Sodium Sulfite

Sodium sulfite is widely used in the pulp and paper industries.
It is used as an oxygen scavenger in water treatment.
It is used to avoid corrosion problems in steam boilers.
As a bleaching agent in the textile industry.
As a dechlorinating and desulfurizing agent as well as in the leather trade.
In the purification of TNT military use.
As a sulfonation agent in the manufacturing of chemicals.
Used to produce sodium thiosulfate.
It is used in froth flotation of ores.
In the recovery of oil.
Used in food preservatives.
Production of dyes.

For more content on various other chemistry topics such as chemical compounds, chemical compound formula – Chemical formula of Plaster of Paris and more visit BYJU’S. You can subscribe to BYJU’S YouTube channel for a clear understanding of the types of bonds.