Sodium sulfite and its use

Chemistry endowed humanity with a mass of useful compounds, greatly facilitating life and opening many new areas previously unknown to people. Among the necessary substances there is also a sodium sulfite, which has found its application in very diverse branches of human activity.

Chemical and physical properties

Sodium sulfite (anhydrous variant) is a white powder, sometimes with a yellowish tinge. It does not burn, does not have the ability to explode, but decomposes when heated, forming toxic gases, which is why it was assigned to the 3rd class of danger. The decomposition products that form the sodium sulfite can disrupt the operation of the central nervous system, if inhaled, cause syncope, reduce the ability to breathe, over-accelerate the rhythm of the heart, cause damage to bones, skin and eyes. That is why in the event of a fire where sodium sulfite is stored, it is necessary to enter there as much as possible protected: in a special suit and necessarily with a breathing apparatus. If the substance is scattered, this place should be protected with a rim from the ground, the powder itself should be covered with something neutral (for example, sand) and only after that it should be collected.

Sodium sulfite is a preservative

Where is this powder used? The substance has very useful chemical properties. Sodium sulfite due to them is used, for example, in the food industry. The fruit-vegetables processed by it are kept longer, not darkening. As a preservative it is used in winemaking and in making sweets, with the help of it make long-stored dried fruits. In this case, it should be noted, in Germany it is forbidden to use sodium sulfite in meat processing, as it masks its stale color, which can lead to mass poisoning.

Other applications

In addition to food, the second main direction of use of this compound is textile, as well as pulp and paper production. Here, the main quantities of sodium sulfite go. But it is used for cleaning water, and for dressing leather. Nim cleanses trinitrotoluene, which is then used in mining or for army purposes. Pharmaceuticals and medicine also do not neglect this substance. A solution of sodium sulfite is more often needed here. The compound referred to here is also used in the production of non-ferrous metals and sodium thiosulfate, which doctors prescribe in cases of poisoning with derivatives of lead, mercury and arsenic.

Obsolete direction

At the time of film photographic and film cameras, sodium sulfite was simply necessary for the development of films proper, preventing the oxidation of solutions and washing the carriers (film or photo paper) away from the latch. Now, with the proliferation of digital analogs, such an application of this substance has remained mainly for fans who have preserved the old technique. Specialists, photographers of the old generation argue that with the development of black and white films, it is sodium sulfite that makes it possible to achieve the most detailed details in the shadows and significantly increases the photosensitivity in the unsuccessful contrast of the negative.

As you can see, this is a substance that is necessary in different areas of human life. And if some direction of its use becomes irrelevant, there is another, no less important.