Is sodium thiosulfate toxic?
Range of Toxicity: A) Ingestion of 12 g of sodium thiosulfate was virtually non-toxic except for producing violent catharsis. B) The lowest toxic intravenous doses for humans were 0.2 to 1.5 g/kg.
Sodium Thiosulfate. Also spelled sodium thiosulphate, this chemical compound (Na2S2O3) is a colorless crystal. Sometimes called a chlorine neutralizer, sodium thiosulfate is used to lower the concentrations of chlorine in pool water.
- Persulfate variation. This clock reaction uses sodium, potassium or ammonium persulfate to oxidize iodide ions to iodine. Sodium thiosulfate is used to reduce iodine back to iodide before the iodine can complex with the starch to form the characteristic blue-black color. Potassium persulfate is less soluble (cfr.
- Starchy solution, such as corn starch (cornflour) in water. Non-starchy solution, such as milk, for comparison. Starchy foods to test: potato (cooked or raw), pasta, rice, or bread. Non-starchy foods for comparison: apple, cucumber, pure sugar (the other main category of carbohydrate), and any others you would like to
- Prescription bottles come in several different colors, the most common of which being orange or light brown due to its ability to prevent ultraviolet light from degrading the potentially photosensitive contents through photochemical reactions, while still letting enough visible light through for the contents to be
Sodium thiosulphate reacts with dilute acid to produce sulphur dioxide, sulphur and water. Combining an acid with a base typically results in water and salt. The reason "why," so to speak, sodium thiosulphate reacts with hydrochloric acid is, in brief, because one is an acid and one is a base.
- The only function of starch in the human diet is to convert into glucose for energy. Starch begins breaking down in your mouth, where saliva surrounds complex starch molecules. As you chew, saliva breaks up starch into simpler carbohydrates called maltose.
- Bananas are a rich source of carbohydrates, mainly starch in unripe bananas and sugars in ripe bananas. Green bananas contain up to 70-80% starch, on a dry weight basis. During ripening, the starch is converted into sugars and ends up being less than 1% when the banana is fully ripe (2).
- Eggs. A whole egg has 6 ounces of protein and no sugar or starch. All of the protein in an egg is in the egg white, and egg whites are fat-free and cholesterol-free. A large egg yolk contains 186 milligrams of cholesterol and no protein.
Redox titration using sodium thiosulfate, Na2S2O3 (usually) as a reducing agent is known as iodometric titration since it is used specifically to titrate iodine. In an iodometric titration, a starch solution is used as an indicator since it can absorb the I2 that is released.
- Starch is often used in chemistry as an indicator for redox titrations where triiodide is present. Starch forms a very dark blue-black complex with triiodide which can be made by mixing iodine with iodide (often from potassium iodide). However, the complex is not formed if only iodine or only iodide (I−) is present.
- The starch indicator is added to the solution near the end of the titration, at the point where dilute iodine imparts a pale yellow color to the solution. First, a diffuse endpoint would result from the slow dissociation of the starch-iodine complex if a large amount of iodine were absorbed in the starch.
- To prepare starch indicator solution, add 1 gram of starch (either corn or potato) into 10 mL of distilled water, shake well, and pour into 100 mL of boiling, distilled water. Stir thoroughly and boil for a 1 minute. Leave to cool down. If the precipitate forms, decant the supernatant and use as the indicator solution.
Updated: 18th November 2019