0.1 Molar Sodium Thiosulfate Solution: Properties and Uses
A 0.1 molar sodium thiosulfate solution is a common laboratory reagent used in various chemical reactions and experiments. In this article, we will discuss the properties, preparation, and uses of a 0.1 molar sodium thiosulfate solution.
Properties of Sodium Thiosulfate
Sodium thiosulfate, also known as sodium hyposulfite, is a colorless, odorless, and crystalline solid with the chemical formula Na<sub>2</sub>S<sub>2</sub>O<sub>3</sub>. It is highly soluble in water, but insoluble in ethanol and other organic solvents. Sodium thiosulfate is a strong reducing agent and is commonly used as an antioxidant in photographic development and as a medication to treat cyanide poisoning.
Preparation of 0.1 Molar Sodium Thiosulfate Solution
To prepare a 0.1 molar sodium thiosulfate solution, you can follow these steps:
Step 1: Calculate the amount of sodium thiosulfate needed
To prepare 1 liter of a 0.1 molar sodium thiosulfate solution, you need to calculate the amount of sodium thiosulfate required. The molar mass of sodium thiosulfate is 158.11 g/mol. To calculate the amount of sodium thiosulfate needed, multiply the molar mass by the desired molarity (0.1 M) and the volume of the solution (1 L).
Amount of sodium thiosulfate needed = Molarity x Molar mass x Volume = 0.1 M x 158.11 g/mol x 1 L = 15.811 g
Step 2: Weigh and dissolve the sodium thiosulfate
Weigh 15.811 g of sodium thiosulfate using a balance and transfer it to a beaker. Add a small amount of distilled water to the beaker and stir until the sodium thiosulfate is completely dissolved.
Step 3: Dilute the solution to the desired volume
Once the sodium thiosulfate is dissolved, add distilled water to the beaker to make up the volume to 1 liter. Stir well to ensure the solution is homogeneous.
Uses of 0.1 Molar Sodium Thiosulfate Solution
A 0.1 molar sodium thiosulfate solution has several uses in various fields, including:
Chemical Reactions
Sodium thiosulfate is a strong reducing agent and is often used to reduce oxidizing agents in chemical reactions. It is commonly used as a reactant in the iodine clock reaction, where it reacts with iodine to form triiodide ions.
Photography
Sodium thiosulfate is used as a fixer in photography to remove unexposed silver halides from photographic film and paper. It converts the silver halides into soluble silver complexes, which can be easily washed away.
Medicine
Sodium thiosulfate is used as an antidote to treat cyanide poisoning. It reacts with cyanide ions to form thiocyanate ions, which are less toxic and can be excreted by the body.
Water Treatment
Sodium thiosulfate is used to remove chlorine and other oxidizing agents from water. It is commonly used in swimming pools and water treatment plants to remove excess chlorine and maintain a healthy water environment.
In conclusion, a 0.1 molar sodium thiosulfate solution is a versatile laboratory reagent with various uses in chemical reactions, photography, medicine, and water treatment. Its strong reducing properties make it an essential component in many applications.
