Table of Contents
- 1 Why do we standardize sodium thiosulphate solution?
- 2 How do you make 0.02 N iodine solution?
- 3 Why sodium thiosulphate is secondary standard?
- 4 Why is KI added in the preparation of iodine?
- 5 What is the purpose of adding sodium thiosulfate at the end of the reaction?
- 6 What are two uses of sodium thiosulfate?
- 7 How much sodium thiosulfate is in 50 mL solution?
- 8 How is sodium thiosulfate standardized against pure iodine?
Why do we standardize sodium thiosulphate solution?
Sodium thiosulphate solution is standardized against potassium dichromate in presence of hydrochloric acid and potassium iodide. The iodine formed in the reaction oxidizes sodium thiosulphate giving sodium tetrathionate ion and the end point is detected by starch solution.
How do you make 0.02 N iodine solution?
Iodine Solution, 0.02 N: Prepare 0.1 N Iodine solution by dissolving 12.7 g of reagent grade iodine (I2) in a solution of 40 g of potassium iodide in 25 mL of deionized water. Transfer to a 1 L volumetric flask, dilute to volume with deionized water and mix.
What is the use of sodium thiosulfate in pharmaceutical analysis?
Sodium thiosulfate, also spelled sodium thiosulphate, is used as a medication to treat cyanide poisoning, pityriasis versicolor, and to decrease side effects from cisplatin. For cyanide poisoning it is often used after the medication sodium nitrite and typically only recommended for severe cases.
Why sodium thiosulphate is secondary standard?
Because it is so prone to absorbing water, it is impossible to accurately measure the mass of a solid sample, so instead it must be put into solution and titrated with a known acidic solution.
Why is KI added in the preparation of iodine?
Molecular iodine is only slightly soluble in water. Adding potassium iodide to iodine in water rapidly converts the molecular iodine (I2) to the much more soluble triiodide ion (I3-).
How do you make 1N iodine solution?
Iodine 0.1 N: Weigh 40 g of potassium iodide (KI) in a 500 mL glass-stoppered flask and dissolve in 100 mL of purified water. Let the solution come to room temperature, add 12.7 g of resublimed iodine (I2), restopper the flask, and swirl the flask until the iodine is completely dissolved.
What is the purpose of adding sodium thiosulfate at the end of the reaction?
The purpose of dechlorination with sodium thiosulfate is to stop the oxidation of nitrite to nitrate with chlorine and determine the concentrations of these constituents.
What are two uses of sodium thiosulfate?
Sodium thiosulfate is used in gold mining, water treatment, analytical chemistry, the development of silver-based photographic film and prints, and medicine. The medical uses of sodium thiosulfate include treatment of cyanide poisoning and pityriasis.
How to prepare a sodium thiosulphate slurry solution?
Dissolve 25 g of sodium thiosulphate in CO2 free water and make the volume upto 1000 ml. Keep the solution aside and filter to remove any cloudieness, if appears. Preparation of starch solution Add one gram of starch to few ml of water, prepare slurry and add gradually to 100 ml of boiling water till a translucent solution will be obtained.
How much sodium thiosulfate is in 50 mL solution?
Each vial contains 12.5 grams of sodium thiosulfate in 50 mL solution (250 mg/mL). Each mL also contains 2.8 mg boric acid and 4.4 mg of potassium chloride. The pH of the solution is adjusted with boric acid and/or sodium hydroxide. Sodium thiosulfate injection is a clear solution with a pH between 7.5 and 9.0.
How is sodium thiosulfate standardized against pure iodine?
Materials. SODIUM THIOSULFATE CAN BE STANDARDIZED AGAINST PURE IODINE DISSOLVED IN KI OR AGAINST IODINE SET FREE FROM AN ACIDIFIED SOLUTION OF KI BY STANDARD SOLUTION OF POTASSIUM PERMANGANATE OR VARIOUS PRIMARY STANDARD OXIDIZING AGENTS SUCH AS POTASSIUM IODATE.
How to calculate the normality of sodium thiosulphate?
Tabulation of standardization Normality of sodium thiosulphate = (Weight of Pot.dichromate)/ (Volume of sod.thiosulfate consumed)× 0.04904