[Kr] 4d105s25p5
2, 8, 18, 18, 7
113.7°C, 236.7°F, 386.9 K
184.4°C, 363.9°F, 457.6 K
Bernard Courtois
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Uses and Properties

Image Explanation

Iodine's role in Betadine showcases its significance in healthcare, from wound care to surgical preparations. The antimicrobial properties of Iodine, harnessed in the Povidone-Iodine complex, contribute to the prevention and treatment of infections, making Betadine a valuable tool in promoting health and hygiene.


A black, shiny, crystalline solid. When heated, iodine sublimes to form a purple vapour.


Iodine: A Versatile Element Weaving Health and Industry

In the expansive realm of chemical elements, iodine, denoted by the symbol I, stands as a versatile and indispensable player with a spectrum of applications ranging from healthcare to industry. This essential element, known for its vibrant purple hue in its elemental state, has woven itself into the fabric of our daily lives, influencing both our well-being and technological progress.


1. Iodine in Human Health: A Crucial Nutrient

At the core of iodine's significance is its fundamental role in human health. Iodine is an essential component of thyroid hormones, which play a pivotal role in regulating metabolism and supporting the growth and development of the human body. Insufficient iodine intake can lead to thyroid disorders, emphasizing the critical importance of this element for overall health.


2. Iodine in Salt: A Public Health Triumph

One of the most successful public health interventions involving iodine is the fortification of table salt. Iodized salt, enriched with iodine, has been instrumental in preventing iodine deficiency disorders worldwide. This simple yet effective measure has significantly reduced the prevalence of conditions such as goiter and intellectual disabilities associated with iodine deficiency.


3. Antiseptic and Disinfectant Applications: Iodine's Healing Touch

Iodine's antiseptic properties make it a stalwart in the field of medicine. Iodine-based antiseptics, such as povidone-iodine found in products like Betadine, are widely used for wound disinfection. These solutions effectively kill a broad spectrum of microorganisms, making them invaluable in preventing infections and promoting the healing of cuts, abrasions, and surgical incisions.


4. Radiocontrast Media in Medical Imaging: Shining Light on Iodine

Iodine compounds are used as radiocontrast agents in medical imaging, particularly in procedures like computed tomography (CT) scans and angiography. These contrast media enhance the visibility of blood vessels and soft tissues, allowing for more accurate diagnosis and visualization of internal structures.


5. Iodine in Pharmaceuticals: Therapeutic Applications

Iodine finds application in various pharmaceutical formulations. Some antifungal and antibacterial medications incorporate iodine for its antimicrobial properties. Additionally, iodine-based compounds are used in the treatment of certain skin conditions and as expectorants in cough syrups.


6. Iodine in Water Purification: Safeguarding Hydration

Iodine's ability to eliminate harmful microorganisms extends to water purification. Iodine tablets or solutions are employed to disinfect water in situations where access to clean water is limited, such as during camping or in emergency situations. This application underscores iodine's role in ensuring safe hydration in diverse environments.


7. Photography and Dyeing: Iodine's Artistic Palette

In the realm of arts and industry, iodine has found applications in photography and dyeing. Silver iodide, a photosensitive compound, is used in traditional photography to capture images. Iodine is also involved in the production of certain dyes, contributing to the vibrant spectrum of colors available in the textile and fashion industries.


8. Iodine in Industrial Processes: Catalysts and Stabilizers

Iodine's unique properties make it valuable in industrial processes. It serves as a catalyst in the production of acetic acid and is employed as a stabilizer in the manufacture of certain polymers. These applications showcase iodine's role in enhancing the efficiency and stability of industrial processes.


9. Nuclear Power Industry: Iodine as a Tracer

In the nuclear power industry, iodine plays a role as a tracer. Radioactive iodine isotopes, such as iodine-131, are used to track the movement of fluids and diagnose potential issues in nuclear power plants. This application contributes to the safety and efficiency of nuclear energy production.


Conclusion: Iodine's Multifaceted Legacy

As we delve into the myriad applications of iodine, from safeguarding human health to catalyzing industrial processes, it becomes clear that this element is truly a linchpin of our modern lives. Its impact extends beyond the laboratory, resonating in the realms of healthcare, photography, industry, and even artistic expression. Iodine's multifaceted legacy is a testament to the versatility and enduring relevance of this elemental gem in shaping the course of human progress.


In the captivating narrative of the periodic table, Iodine, symbolized by the letter I, emerges as a distinctive and historically significant element with a journey that spans centuries. From its humble discovery to its pivotal role in healthcare and industry, Iodine's story weaves through the annals of science, leaving an indelible mark on human progress.


1. Alchemical Intrigues: The Early Glimpses of Element I

The history of Iodine is entwined with the mystique of alchemy, where early practitioners sought the philosopher's stone and the transmutation of base metals. While Iodine itself wasn't identified at this stage, its presence in compounds like sal ammoniac was noted in alchemical texts. The alchemists, driven by symbolism and experimentation, laid the groundwork for the eventual isolation of this remarkable element.


2. Discovery and Isolation: The 19th-Century Unveiling

Iodine's true identity began to unfold in the early 19th century. The breakthrough came in 1811 when French chemist Bernard Courtois discovered a violet-colored substance while extracting sodium carbonate from seaweed ash. This substance exhibited remarkable properties, including a distinctive color and the ability to form compounds with metals. Courtois, alongside chemists Charles Bernard Desormes and Nicolas Clément, recognized this as a new element, and Iodine was officially isolated in 1813 by Joseph Louis Gay-Lussac.


3. The Medicinal Marvel: Iodine in the 19th Century

As Iodine took its place in the realm of known elements, its medicinal properties became a subject of intense exploration. In the 19th century, Iodine was hailed for its potential therapeutic applications, and iodine tinctures gained popularity as antiseptics. Pioneering physicians, including the renowned Dr. Jean Lugol, introduced Lugol's solution, a medicinal preparation containing Iodine, which found use in treating various conditions.


4. Iodine Deficiency: A Silent Health Crisis

While Iodine's medicinal applications were gaining traction, a new chapter unfolded in the 20th century with the recognition of iodine deficiency disorders (IDD). The lack of sufficient iodine in diets led to conditions like goiter, cretinism, and intellectual disabilities. Efforts to combat IDD gained momentum with the introduction of iodized salt, a simple yet effective solution that transformed public health globally.


5. World War I and II: Iodine in Military Medicine

Iodine's antiseptic properties found extensive use during World War I and II. Iodine-based solutions were employed for wound disinfection, and the element played a crucial role in preventing infections on the battlefield. This wartime application highlighted the importance of Iodine in military medicine and paved the way for further advancements in healthcare.


6. Nuclear Medicine: Iodine as a Diagnostic Tool

In the mid-20th century, Iodine's properties took on a new dimension with its use in nuclear medicine. Radioactive isotopes of Iodine, particularly iodine-131, became vital tools for diagnostic imaging. These isotopes were employed to trace the function of the thyroid gland and detect abnormalities, contributing to advancements in medical diagnostics.


7. Iodine in Industry: Catalysts and Beyond

As industrial processes evolved, Iodine found applications beyond medicine. It became a catalyst in the production of acetic acid and was utilized as a stabilizer in the polymer industry. These industrial applications showcased Iodine's versatility and its ability to contribute to the efficiency of various manufacturing processes.


8. Contemporary Applications: Iodine in the 21st Century

In the 21st century, Iodine continues to play a vital role in various fields. From its presence in antiseptics and pharmaceuticals to its use in water purification and as a component in contrast media for medical imaging, Iodine remains an elemental force driving progress in health and technology.


Conclusion: Iodine - A Journey Unveiling Layers of Significance

The history of Iodine is a tapestry woven with scientific curiosity, medical breakthroughs, and industrial applications. From alchemical musings to contemporary contributions in healthcare and industry, Iodine's journey is a testament to the enduring impact of chemical elements on the trajectory of human knowledge and well-being. As we continue to unveil the layers of significance embedded in this essential element, Iodine remains a symbol of both historical curiosity and modern innovation.

Atomic Data

Atomic Radiues, Non-bonded (A): 1.98
Electron Affinity (kJ mol-1): 295.152
Covalent Radiues (A): 1.36
Electronegativity (Pauling Scale): 2.66
Ionisation Energies (kJ mol-1) 1st 2nd 3rd 4th 5th 6th 7th 8th
1008.393 1845.89 3184 - - - - -

Oxidation States and Isotopes

Common oxidation states 7, 5, 1, -1
Isotope Atomic Mass Natural Abundance Half Life Mode of Decay
127I 126.904 100 - -

Supply Risk

Relative Supply Risk: 6.5
Crustal Abundance (ppm): 0.71
Recycle Rate (%): Unknown
Production Conc.(%) : 59.7
Top 3 Producers:
1) Chile
2) Japan
3) USA
Top 3 Reserve Holders:
1) Chile
2) Japan
3) USA
Substitutability: Unknown
Political Stability of Top Producer: 67.5
Political Stability of Top Reserve Holder: 67.5

Pressure and Temperature Data

Specific Heat Capacity: 214
Shear Modulus: Unknown
Young Modulus: Unknown
Bulk Modulus: 7.7
Pressure 400k Pressure 600k Pressure 800k Pressure 1000k Pressure 1200k Pressure 1400k Pressure 1600k Pressure 1800k Pressure 2000k Pressure 2200k Pressure 2400k
- - - - - - - - - - 7.7


Transcript :

Iodine is a non-metallic element. This substance belongs to the halogen family. Iodine's molecular mass is calculated to be 126.9 grams per. It is a nutrient that is absolutely necessary for humans, since this element is required by each and every cell in the body. Iodine is prsent in many foods. Among the most common sources of Iodine are fish, seafood, and dairy products.

In the early 19th century, Bernard Courtois, a French chemist, accidentally discovered this element. He was experimenting with saltpeter, a key component in gunpowder. In the year 1811, following the Napoleonic Wars that were taking place in France, it was found by accident. Iodine's discovery is an interesting episode in the history of the evolution of chemical technology. It led to the development of new production methods, as well as a drastic change in the raw materials that were used. The Discovery of Iodine is a significant milestone in the development of scientific knowledge and innovation. The name iode was first suggested by French chemist Joseph-Louis Gay-Lussac. He gave the element its name following the Greek term iodes, which translates to "violet". Gay-Lussac's study of Iodine continued for the next two years. During this time, he discovered Iodine's chemical properties and began its extraction from seaweed.

A year after the discovery, Humphrey Davy also isolated the element from seaweed and later claimed to have found it eight days earlier. However, Iodine had been known to have medicinal properties by 1820s.

Iodine is a fairly rare element, but there are numerous sources of this essential mineral. It occurs in seawater, soil, air and rocks. Additionally, it may be found in the outermost layer of the earth’s crust. The thyroid gland is responsible for storing the majority of it. In the kitchen, it is added to salt seasonings and processed foods made of iodine-enriched wheat flour contain 0.05 mg to 40 mg of iodine per 100 grams of wheat flour. The United States Food and Drug Administration recommends 150 micrograms of Iodine a day. Having an Iodine deficiency is a problem in some parts of the world, including the tropics and semi-arid equatorial regions.

Iodine is a poisonous halogen element with a distinctive odor. The element has a blue-violet color. The atom's first ionization potential is about 1008.39 kJ/mol. it has a melting point of 113.7 degrees Celsius. Iodine is usually found in the gaseous form, but in the solid state it has a crystalline, glittering appearance. It can occur in oxidation states of -1 or +7. Depending on its oxidation state, Iodine can be either a Lewis acid or an iodate. Generally speaking, it is the most electropositive halogen after astatine.

Among its properties, this element is the least reactive halogen, meaning that it does not react strongly with other elements. In solution, Iodine combines with Lewis bases. This makes the compound unstable and it can dissolve in acid. Iodine monochloride is a relatively underused halogenating agent. Its aqueous chemistry is similar to that of bromine. It dissolves in chloroform and carbon tetrachloride. This compound, which is a strong reducing agent, may be the basis for certain reactions. Furthermore, it can react with fluorine to produce interhalogen compounds. Similarly, it can react with chlorine to produce hypoiodite ions.

Iodine plays an important role in the manufacture of both food and chemical goods. It is also commonly used in imaging techniques, such as as an internal contrasting agent. This element is used to treat a wide range of diseases, both internal and external. Aside from its medicinal use, Iodine has also played a role in the development of manufacturing technology. It is most often used when it is prepared in the form of a tinctures. This small bottle is a good way to sanitize drinking water, or disinfect wounds. Iodine is used as an analytical reagent for various chemicals. Several Iodine compounds are in use in industry, medicine and chemical research. They include polyvalent Iodine and hypervalent Iodine.

Iodine has been used in medical applications, such as as a radiocontrast agent in X-ray imaging and as an antiseptic for cuts and wounds. Another medication is Lugol's Iodine. Iodine-131, the radioactive isotope is an excellent contrasting tool for both detecting and managing thyroid cancer.


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