The 2% sodium disulfite or sodium metabisulfite solution is a chemical compound used in various applications. Sodium disulfite (Na2S2O5)functions as a reducing agent and is capable of removing oxygen and reducing colors.

In histology and cytology, the 2% sodium disulfite or sodium metabisulfite solution is often used as a reducing agent for dyes such as silver nitrate to remove excess silver and control color intensity. It is also used as a bleaching agent to remove unwanted color from histological sections before they are re-stained.

The 2% sodium disulfite or sodium metabisulfite solution also finds application in photography as a reducing agent in fixing baths to remove unexposed silver halide and stabilize the image. In the food industry, sodium metabisulfite is used as a preservative and antioxidant.

Please note that sodium disulfite and sodium metabisulfite are considered irritants to the skin, eyes and respiratory system. Therefore, appropriate protective measures should be taken when working with these chemicals.