Information about Potassium Iodide
| Potassium iodide | |
|---|---|
) | |
) | |
| IUPAC name | Potassium iodide |
| Other names | Kalium iodide, knollide, potide |
| Identifiers | |
| CAS number | |
| RTECS number | TT2975000 |
| Properties | |
| Molecular formula | KI |
| Molar mass | 166.00 g/mol |
| Appearance | white crystalline solid |
| Density | 3.13 g/cm3, solid |
| Melting point | 681 °C (954 K) |
| Boiling point | 1330 °C (1603 K) |
| Solubility in water | 128 g/100 ml (6 °C) |
| Hazards | |
| MSDS | External MSDS |
| Main hazards | Slightly hazardous |
| NFPA 704 |
|
| R-phrases | 36, 38, 42-43, 61 |
| S-phrases | 26, 36-37, 39, 45 |
| Related Compounds | |
| Other anions | potassium bromide potassium chloride |
| Other cations | lithium iodide sodium iodide rubidium iodide caesium iodide |
| Except where noted otherwise, data are given for materials in their standard state (at 25 C, 100 kPa) | |
)
Potassium iodide is a white crystalline salt with chemical formula KI, used in photography and radiation treatment. It finds widespread application as an iodide source because it is less hygroscopic than sodium iodide, making it easier to work with. KI can turn yellow upon heating in air or upon standing in moist air for long periods, because of oxidation of the iodide to iodine.
Chemical properties
Potassium iodide behaves as a simple ionic salt, K+I−. Since the iodide ion is a mild reducing agent, I− is easily oxidised to I2 by powerful oxidising agents such as chlorine:2 KI(aq) + Cl2(aq) → 2 KCl + I2(aq)
Even air will oxidize iodide as evidenced by the observation of a purple extract when KI is rinsed with dichloromethane. Under acidic conditions, KI is oxidised even more easily, due to the formation of hydroiodic acid (HI), which is a powerful reducing agent.[1][2][3][4]
KI forms I3− when combined with elemental iodine. Unlike I2, I3− salts can be highly water-soluble. I2 and I3− have virtually identical redox potentials (0.535 and 0.536 V vs NHE, respectively), i.e. they are both mild oxidants relative to H2. Therefore, this reaction allows the iodine to be used in aqueous solutions for redox titrations.
Potassium iodide also serves in some organic reactions as a source of iodide ion (see "uses" below).
Uses
Potassium iodide is used in photography, in the preparation of silver(I) iodide for high speed photographic film:KI(aq) + AgNO3(aq) → AgI(s) + KNO3(aq)
Potassium iodide is also added to table salt in small quantities to make it "iodized". In a saturated solution, it is also used as an expectorant to treat lung congestion.
KI is often used as a source of iodide ion in organic synthesis. A useful application is in the preparation of aryl iodides from arenediazonium salts.[5][6] For example:
)
Saturated solution of potassium iodide is also used as treatment for sporotrichosis, a fungal infection.
In medical use, it can also serve as an antiseptic for people suffering from sore throat. The dose is 0.5g-1.0g in 100mL, with the accompany of iodine (0.5g-1.0g in 100mL).
KI is also used as a fluorescence quenching agent in biomedical research because of collisional quenching by its iodide ion.
In aqueous solution with elemental iodine, it acts as a gold etchant and will attack and dissolve gold surfaces.
Radiation protection
)
An unopened box of Potassium iodate tablets, produced and distributed to the population of the Republic of Ireland in case of a terror attack on the Sellafield nuclear power station in the United Kingdom.
| Age | KI in mg | KIO3 in mg |
|---|---|---|
| Over 12 years old | 130 | 170 |
| 3 - 12 years old | 65 | 85 |
| 1 - 36 months old | 32 | 42 |
| < 1 month old | 16 | 21 |
See fission products and the external links for more details.
Precautions
Mild irritant, wear gloves. Chronic overexposure can have adverse effects on the thyroid.References
1. ^ N. N. Greenwood, A. Earnshaw, Chemistry of the Elements, Pergamon Press, Oxford, UK, 1984
2. ^ Handbook of Chemistry and Physics, 71st edition, CRC Press, Ann Arbor, Michigan, 1990
3. ^ The Merck Index, 7th edition, Merck & Co., Rahway, New Jersey, 1960
4. ^ H. Nechamkin, The Chemistry of the Elements, McGraw-Hill, New York, 1968
5. ^ L. G. Wade, Organic Chemistry, 5th ed., pp. 871-2, Prentice Hall, Upper Saddle RIver, New Jersey, 2003
6. ^ J. March, Advanced Organic Chemistry, 4th ed., pp. 670-1, Wiley, New York, 1992
7. ^ Plan B for anyone caught without KI or KIO3 tablets in a nucleair emergency. Retrieved on 2007-03-16.
8. ^ World Health Organization, Guidelines for Iodine Prophylaxis following Nuclear Accidents, Update 1999
2. ^ Handbook of Chemistry and Physics, 71st edition, CRC Press, Ann Arbor, Michigan, 1990
3. ^ The Merck Index, 7th edition, Merck & Co., Rahway, New Jersey, 1960
4. ^ H. Nechamkin, The Chemistry of the Elements, McGraw-Hill, New York, 1968
5. ^ L. G. Wade, Organic Chemistry, 5th ed., pp. 871-2, Prentice Hall, Upper Saddle RIver, New Jersey, 2003
6. ^ J. March, Advanced Organic Chemistry, 4th ed., pp. 670-1, Wiley, New York, 1992
7. ^ Plan B for anyone caught without KI or KIO3 tablets in a nucleair emergency. Retrieved on 2007-03-16.
8. ^ World Health Organization, Guidelines for Iodine Prophylaxis following Nuclear Accidents, Update 1999
External links
Antidotes (V03AB) |
|---|
| Ipecacuanha - Nalorphine - Edetates - Oximes (Pralidoxime, Obidoxime) - Prednisolone/promethazine - Thiosulfate - Sodium nitrite - Dimercaprol - Protamine - Naloxone - Ethanol - Methylthioninium chloride - Potassium permanganate - Physostigmine - Copper sulfate - Potassium iodide - Amyl nitrite - Acetylcysteine - Digitalis antitoxin - Flumazenil - Methionine - 4-Dimethylaminophenol - Cholinesterase - Prussian blue - Glutathione - Hydroxocobalamin - Fomepizole |
IUPAC nomenclature is a system of naming chemical compounds and of describing the science of chemistry in general. It is developed and kept up to date under the auspices of the International Union of Pure and Applied Chemistry (IUPAC).
..... Click the link for more information.
..... Click the link for more information.
CAS registry numbers are unique numerical identifiers for chemical compounds, polymers, biological sequences, mixtures and alloys. They are also referred to as CAS numbers, CAS RNs or CAS #s.
..... Click the link for more information.
..... Click the link for more information.
A chemical formula is a concise way of expressing information about the atoms that constitute a particular chemical compound. A chemical formula is also a short way of showing how a chemical reaction occurs.
..... Click the link for more information.
..... Click the link for more information.
Molar mass, symbol M,[1] is the mass of one mole of a substance (chemical element or chemical compound).[2] It is a physical property which is characteristic of each pure substance.
..... Click the link for more information.
..... Click the link for more information.
In physics, density is mass m per unit volume V—how heavy something is compared to its size. A small, heavy object, such as a rock or a lump of lead, is denser than a lighter object of the same size or a larger object of the same weight, such as pieces of
..... Click the link for more information.
..... Click the link for more information.
The melting point of a crystalline solid is the temperature range at which it changes state from solid to liquid. Although the phrase would suggest a specific temperature and is commonly and incorrectly used as such in most textbooks and literature, most crystalline compounds
..... Click the link for more information.
..... Click the link for more information.
boiling point of a liquid is the temperature at which the vapor pressure of the liquid equals the environmental pressure surrounding the liquid.[1][2][3][4]
..... Click the link for more information.
..... Click the link for more information.
Solubility is a physical property referring to the ability for a given substance, the solute, to dissolve in a solvent.[1] It is measured in terms of the maximum amount of solute dissolved in a solvent at equilibrium. The resulting solution is called a saturated solution.
..... Click the link for more information.
..... Click the link for more information.
Water is a common chemical substance that is essential to all known forms of life.[1] In typical usage, water refers only to its liquid form or state, but the substance also has a solid state, ice, and a gaseous state, water vapor.
..... Click the link for more information.
..... Click the link for more information.
Occupational safety and health (OSH) is a cross-disciplinary area concerned with protecting the safety, health and welfare of people engaged in work or employment. As a secondary effect, OSH may also protect co-workers, family members, employers, customers, suppliers, nearby
..... Click the link for more information.
..... Click the link for more information.
NFPA 704 is a standard maintained by the U.S. National Fire Protection Association. It defines the colloquial "fire diamond" used by emergency personnel to quickly and easily identify the risks posed by nearby hazardous materials.
..... Click the link for more information.
..... Click the link for more information.
R-phrases (short for Risk Phrases) are defined in Annex III of European Union Directive 67/548/EEC: Nature of special risks attributed to dangerous substances and preparations.
..... Click the link for more information.
..... Click the link for more information.
S-phrases are defined in Annex IV of European Union Directive 67/548/EEC: Safety advice concerning dangerous substances and preparations. The list was consolidated and republished in Directive 2001/59/EC , where translations into other EU languages may be found.
..... Click the link for more information.
..... Click the link for more information.
ion is an atom or molecule which has lost or gained one or more electrons, making it positively or negatively charged. A negatively charged ion, which has more electrons in its electron shells than it has protons in its nuclei, is known as an anion
..... Click the link for more information.
..... Click the link for more information.
Potassium bromide (KBr) is a salt, widely used as an anticonvulsant and a sedative in the late 19th and early 20th centuries. Its action is due to the bromide ion (sodium bromide is equally effective).
..... Click the link for more information.
..... Click the link for more information.
The chemical compound potassium chloride (KCl) is a metal halide composed of potassium and chlorine. In its pure state it is odorless. It has a white or colorless vitreous crystal, with a crystal structure that cleaves easily in three directions.
..... Click the link for more information.
..... Click the link for more information.
ion is an atom or molecule which has lost or gained one or more electrons, making it positively or negatively charged. A negatively charged ion, which has more electrons in its electron shells than it has protons in its nuclei, is known as an anion
..... Click the link for more information.
..... Click the link for more information.
Lithium iodide, or LiI, is a compound of lithium and iodine. When exposed to air, it becomes yellow in color, due to the liberation of the iodine.[2]
..... Click the link for more information.
Applications
Lithium iodide is used as an electrolyte for high temperature batteries...... Click the link for more information.
Sodium iodide is a white, crystalline salt with chemical formula NaI used in radiation detection, treatment of iodine deficiency, and as a reactant in the Finkelstein reaction.
H2O 184
Liquid ammonia 162
Liquid sulfur dioxide 15
Methanol 62.5 - 83.
..... Click the link for more information.
H2O 184
Liquid ammonia 162
Liquid sulfur dioxide 15
Methanol 62.5 - 83.
..... Click the link for more information.
Caesium iodide (CsI) is an ionic compound often used as the input phosphor of an x-ray image intensifier tube found in fluoroscopy equipment.
An important application of caesium iodide crystals, which are scintillators, is electromagnetic calorimetry in experimental
..... Click the link for more information.
An important application of caesium iodide crystals, which are scintillators, is electromagnetic calorimetry in experimental
..... Click the link for more information.
standard state of a material is its state at 1 bar (100 kilopascals exactly). This pressure was changed from 1 atm (101.325 kilopascals) by IUPAC in 1990.[1] The standard state of a material can be defined at any given temperature, most commonly 25 degrees Celsius,
..... Click the link for more information.
..... Click the link for more information.
CRYSTAL is a quantum chemistry ab initio program, designed primarily for calculations on crystals (3 dimensions), slabs (2 dimensions) and polymers (1 dimension) using translational symmetry, but it can be used for single molecules.[1] It is written by V.R. Saunders, R.
..... Click the link for more information.
..... Click the link for more information.
Salt is a mineral essential for animal life, composed primarily of sodium chloride. Salt for human consumption is produced in different forms: unrefined salt (such as sea salt), refined salt (table salt), and iodized salt.
..... Click the link for more information.
..... Click the link for more information.
A chemical formula is a concise way of expressing information about the atoms that constitute a particular chemical compound. A chemical formula is also a short way of showing how a chemical reaction occurs.
..... Click the link for more information.
..... Click the link for more information.
Potassium (IPA: /pə(ʊ)ˈtasiəm/, /pə'tæsiəm/) is a chemical element. It has the symbol K (Arabic: al qalja
..... Click the link for more information.
..... Click the link for more information.
Iodine (IPA: /ˈaɪədaɪn, ˈaɪədɪn/, or /ˈaɪədiːn/; from Greek: iodes
..... Click the link for more information.
..... Click the link for more information.
Photography [fә'tɑgrәfi:],[foʊ'tɑgrәfi:] is the process of recording pictures by means of capturing light on a light-sensitive medium, such as a film or electronic sensor.
..... Click the link for more information.
..... Click the link for more information.
Hygroscopy is the ability of a substance to attract water molecules from the surrounding environment through either absorption or adsorption.
Hygroscopic substances include honey, glycerin, ethanol, methanol, concentrated sulfuric acid, methamphetamine, and concentrated
..... Click the link for more information.
Hygroscopic substances include honey, glycerin, ethanol, methanol, concentrated sulfuric acid, methamphetamine, and concentrated
..... Click the link for more information.
Sodium iodide is a white, crystalline salt with chemical formula NaI used in radiation detection, treatment of iodine deficiency, and as a reactant in the Finkelstein reaction.
H2O 184
Liquid ammonia 162
Liquid sulfur dioxide 15
Methanol 62.5 - 83.
..... Click the link for more information.
H2O 184
Liquid ammonia 162
Liquid sulfur dioxide 15
Methanol 62.5 - 83.
..... Click the link for more information.
Redox (shorthand for reduction/oxidation reaction) describes all chemical reactions in which atoms have their oxidation number (oxidation state) changed.
This can be either a simple redox process such as the oxidation of carbon to yield carbon dioxide, or the
..... Click the link for more information.
This can be either a simple redox process such as the oxidation of carbon to yield carbon dioxide, or the
..... Click the link for more information.
This article is copied from an article on Wikipedia.org - the free encyclopedia created and edited by online user community. The text was not checked or edited by anyone on our staff. Although the vast majority of the wikipedia encyclopedia articles provide accurate and timely information please do not assume the accuracy of any particular article. This article is distributed under the terms of GNU Free Documentation License.
Herod_Archelaus
