Description

Potassium iodide is an inorganic compound with the chemical formula KI. This white salt is the most commercially significant iodide compound.

Specifications of Potassium Iodide Commercial Pure:

Appearance: White Powder
Assay: *9.0% min KI
Insoluble Matter: 0.**5% max
Loss on drying: 0.2%  max at **0C
pH of 5% solution: 6.0 TO 9.2 at *5C
Chlorides & Bromides: 0.*1% as Cl
Iodate (IO3): 3 ppm max
Phosphate (PO4): 0.**1% max
Sulfate (SO4): 0.**5% max
Barium (Ba): 0.**2% max
Heavy Metals (Pb): 5 PPM max
Iron (Fe): 3 PPM max
Calcium (Ca): 0.**2% max
Magnesium (Mg): 0.**1% max
Sodium (Na): 0.**5% max

Potassium Iodide USP
KI *- **6.*0
Potassium iodide *- [********0]

Potassium Iodide contains not less than *9.0 percent and not more than **1.5 percent of KI, calculated on the dried basis.

Identification— A solution of it meets the requirements of the tests for Potassium and for Iodide.
Alkalinity— Dissolve 1.0 g in *0 mL of water, and add 0.1 mL of 0.1 N sulfuric acid and 1 drop of phenolphthalein TS: no color is produced.
Loss on drying— Dry it at **5C for 4 hours: it loses not more than 1.0% of its weight.
Iodate— Dissolve 1.1 g in sufficient ammonia- and carbon dioxide-free water to obtain *0 mL of solution, and transfer to a color-comparison tube. Add 1 mL of starch TS and 0.*5 mL of 1.0 N sulfuric acid, mix, and compare the color with that of a control containing, in a similar volume, **0 mg of Potassium Iodide, 1 mL of standard iodate solution [prepare by diluting 1 mL of potassium iodate solution (1 in ***0) with water to **0 mL], 1 mL of starch TS, and 0.*5 mL of 1.0 N sulfuric acid. Any color produced in the solution of the test specimen does not exceed that in the control: not more than 4 µg per g is found.
Limit of nitrate, nitrite, and ammonia— To a solution of 1 g in 5 mL of water contained in a test tube of about **-mL capacity add 5 mL of 1 N sodium hydroxide and about **0 mg of aluminum wire. Insert a pledget of purified cotton in the upper portion of the test tube, and place a piece of moistened red litmus paper over the mouth of the tube. Heat the test tube and its contents in a steam bath for *5 minutes: no blue coloration of the paper is discernible.
Thiosulfate and barium— Dissolve 0.5 g in *0 mL of ammonia- and carbon dioxide-free water, and add 2 drops of 2 N sulfuric acid: no turbidity develops within 1 minute.
Heavy metals— Dissolve 2.0 g in *5 mL of water: the limit is 0.**1%.
Assay— Dissolve about **0 mg of Potassium Iodide, accurately weighed, in about *0 mL of water, and add *5 mL of hydrochloric acid. Titrate with 0.*5 M potassium iodate VS until the dark brown solution which is produced becomes pale brown. Add 2 to 3 drops of amaranth TS, and continue the titration slowly until the red color just changes to yellow. Each mL of 0.*5 M potassium iodate is equivalent to *6.*0 mg of KI.

Potassium Iodide BP (Ph Eur monograph ***6)
KI *- **6.0 *- ********0

Content:*9.0 per cent to **0.5 per cent (dried substance).

CHARACTERS
Appearance: White or almost white powder or colourless crystals.
Solubility: Very soluble in water, freely soluble in glycerol, soluble in ethanol (*6 per cent).

IDENTIFICATION
A. Solution S (see Tests) gives the reactions of iodides (2.3.1).
B. Solution S gives the reactions of potassium (2.3.1).

TESTS
Solution S: Dissolve *0.0 g in carbon dioxide-free water R prepared from distilled water R and dilute to **0 ml with the same solvent.
Appearance of solution: Solution S is clear and colourless.
Alkalinity: To *2.5 ml of solution S add 0.1 ml of bromothymol blue solution R1. Not more than 0.5 ml of 0.*1 M hydrochloric acid is required to change the colour of the indicator.
Iodates: To *0 ml of solution S add 0.*5 ml of iodide-free starch solution R and 0.2 ml of dilute sulphuric acid R and allow to stand protected from light for 2 min. No blue colour develops.
Sulphates: Maximum **0 ppm.
Dilute *0 ml of solution S to *5 ml with distilled water R.
Thiosulphates: To *0 ml of solution S add 0.1 ml of starch solution R and 0.1 ml of 0.**5 M iodine. A blue colour is produced.
Iron: Maximum *0 ppm.
Dilute 5 ml of solution S to *0 ml with water R.
Heavy metals: Maximum *0 ppm.
*2 ml of solution S complies with test A. Prepare the reference solution using lead standard solution (1 ppm Pb) R.
Loss on drying: Maximum 1.0 per cent, determined on 1.*0 g of previously powdered substance by drying in an oven at **5C for 3 h.

POTASSIUM IODIDE IP
KI *- Mol. Wt. **6.*0

Category: Antithyroid; antifungal; expectorant.
Description: Colourless crystals or white powder; odourless
Solubility: Very soluble in water; freely soluble in glycerin; soluble in ethanol (*5%).

STANDARDS
Potassium Iodide contains not less than *9.0 per cent and not more than **0.5 per cent of KI, calculated with reference to the dried substance.
Identification: A *0% w/v solution in carbon dioxide-free water (solution A) gives the reactions of potassium salts and of iodides.
Alkalinity: To *0 ml of solution A add 0.2 ml of 0.*1M sulphuric acid; no colour is produced on addition of a drop of phenolphthalein solution. .
Clarity and colour of solution: Solution A is clear and colourless.
Arsenic: Dissolve 5.0 g in *0 ml of \'water and *2 ml of stannated hydrochloric acid AsT. The resulting solution complies with the limit test for arsenic (2 ppm).
Heavy metals: Not more than *0 ppm, determined on 2.0 g
Iron: Solution A complies with the limit lest for iron (*0 ppm).
Barium: Dissolve 0.5 g in *0 ml of water and add 1 ml of dilute sulphuric acid; no turbidity develops within one minute.

Potassium Iodide FCC Food Grade
KI Formula wt **6.*0
CAS: [********0]

DESCRIPTION
Potassium Iodide occurs as hexahedral crystals, either transparent and colorless or somewhat opaque and white, or as a white, granular powder. It is stable in dry air but slightly hygroscopic in moist air. One gram is soluble in 0.7 mL of water at *5°, in 0.5 mL of boiling water, in 2 mL of glycerin, and in *2 mL of alcohol.

REQUIREMENTS
Identification:
A. A 1:*0 aqueous solution responds to the tests for Potassium and for Iodide.
B. The pH of a 1:*0 aqueous solution is between 6 and *0.
Assay: Not less than *9.0% and not more than **1.5% of KI after drying.
Iodate: Not more than 4 mg/kg.
Lead: Not more than 4 mg/kg.
Loss on Drying: Not more than 1%.
Nitrate, Nitrite, and Ammonia: Passes test.
Thiosulfate and Barium: Passes test.

Potassium Iodide ACS AR Analytical Reagent Grade Chemical

KI *- Formula Weight **6.*0
CAS Number ********0

REQUIREMENTS
Assay: Minimum *9.0% KI
pH of a 5% solution: 6.**9.2 at *5C

MAXIMUM ALLOWABLE
Insoluble matter: 0.**5%
Loss on drying at **0C: 0.2%
Chloride and bromide (as Cl): 0.*1%
Iodate (IO3): 3 ppm
Nitrogen compounds (as N): 0.**1%
Phosphate (PO4): 0.**1%
Sulfate (SO4): 0.**5%
Barium (Ba): 0.**2%
Heavy metals (as Pb): 5 ppm
Iron (Fe): 3 ppm
Calcium (Ca): 0.**2%
Magnesium (Mg): 0.**1%
Sodium (Na): 0.**5%

Potassium iodide is a precursor to silver iodide (AgI) an important chemical in photography. KI is a component in some disinfectants and hair treatment chemicals. KI is also used as a fluorescence quenching agent in biomedical research.

The major uses of KI include use as a nutritional supplement in animal feeds and also the human diet. It is the most common additive used to "iodize" table salt, a public health measure to prevent iodine deficiency in populations which get little seafood. The oxidation of iodide causes slow loss of iodine content from iodized salts that are exposed to excess air. Potassium iodide is also used in several pharmaceutical preparations and for protection against nuclear radiation.