Sodium thiosulphate

Sodium thiosulphate (also spelled sodium thiosulfate) is a chemical compound with the formula Na2S2O3. It is a white crystalline solid that is soluble in water and is often used in a variety of industrial and medical applications.

Chemical properties

Sodium thiosulphate is an inorganic compound that is typically found in the pentahydrate form, which means it has five water molecules attached to each formula unit. It is a colorless or white crystalline solid that is readily soluble in water. The compound is stable under normal conditions, but it can decompose when heated.

Uses

Sodium thiosulphate has a wide range of uses in various industries. In the photography industry, it is used as a photographic fixer, which helps to remove unexposed silver halides from photographic negatives. In the medical field, it is used as an antidote for cyanide poisoning. It is also used in water treatment to dechlorinate tap water, and in the tanning industry to reduce chrome VI to chrome III.

Health effects

While sodium thiosulphate is generally considered safe for use, it can cause side effects in some individuals. These can include nausea, vomiting, and diarrhea. In rare cases, it can cause serious allergic reactions.

See also

• Thiosulfate
• Sodium sulfate
• Sodium bisulfite