Cadmium

8.69
112.414
[Kr] 4d105s2
114Cd
12
5
d
48
2, 8, 18, 18, 2
867.772
Cd
8.69
321.069°C, 609.924°F, 594.219 K
767°C, 1413°F, 1040 K
Friedrich Stromeyer
1817
7440-43-9
22410
More Information
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Uses and Properties

Image Explanation

Utilized in the fabrication of photoconductive devices, Cadmium finds its application notably in the creation of Cadmium sulfide (CdS). CdS, recognized as a light-dependent resistor (LDR), plays a pivotal role in photoconductive applications by altering its electrical resistance in reaction to fluctuations in the intensity of incident light.

Appearance

Cadmium is a silvery metal with a bluish tinge to its surface.

Uses

Unveiling the Versatility of Cadmium: Beyond Controversy, Embracing Utility


Cadmium, a naturally occurring element with a distinctive bluish-white hue, has long been a subject of both fascination and controversy. While its toxic properties have raised concerns, Cadmium also boasts a range of valuable applications across diverse industries. This article delves into the multifaceted uses of Cadmium, highlighting its contributions to technology, manufacturing, and energy sectors, while acknowledging the importance of responsible usage and environmental considerations.

 

1. Cadmium in Batteries: Powering the Portable Revolution


Cadmium's role in batteries has been pivotal, particularly in rechargeable nickel-cadmium batteries (NiCd). These batteries, widely used in portable electronic devices, power tools, and emergency backup systems, owe their efficiency to Cadmium. Its ability to provide a stable voltage and withstand numerous charge-discharge cycles has made NiCd batteries a reliable choice for applications where longevity and consistency are paramount.

While advancements in battery technology have introduced alternative materials, the historical significance of Cadmium in portable power solutions cannot be understated.

 

2. Cadmium in Pigments: Vibrancy in Art and Industry


Cadmium compounds are renowned for their vivid coloration, and as such, they have been extensively used in pigments for paints and plastics. Cadmium-based pigments, known for their vibrant reds, yellows, and oranges, have been a staple in the art world for decades. Artists and manufacturers alike appreciate the stability and brilliance that Cadmium pigments bring to their creations.

However, the environmental impact of these pigments has led to a shift towards eco-friendly alternatives in recent years, emphasizing the importance of responsible choices in the creative industry.

 

3. Cadmium in Solar Cells: Harnessing the Power of the Sun


The quest for sustainable energy sources has propelled Cadmium into the realm of photovoltaic technology. Cadmium telluride (CdTe) solar cells have emerged as an efficient and cost-effective alternative to traditional silicon-based cells. CdTe solar panels demonstrate high conversion efficiency and are particularly suitable for large-scale solar energy projects, contributing to the global shift towards renewable energy sources.

Cadmium's presence in solar technology underscores its adaptability to emerging environmental challenges.

 

4. Cadmium in Plating: Protecting and Enhancing Surfaces


Cadmium's corrosion resistance and ability to adhere well to various substrates make it a valuable material in electroplating applications. Cadmium plating is utilized to protect metals from corrosion, enhance their durability, and provide a smooth, lustrous finish. Aircraft components, fasteners, and certain automotive parts benefit from Cadmium plating, ensuring longevity and reliability in harsh environments.

However, the environmental impact of Cadmium plating has led to increased scrutiny, prompting industries to explore alternative coating technologies.

 

5. Cadmium in Nuclear Reactors: A Role in Power Generation


Cadmium's neutron-absorbing properties make it useful in control rods within nuclear reactors. These rods, often made of cadmium or its alloys, help regulate the rate of nuclear reactions by absorbing excess neutrons. The controlled use of Cadmium in nuclear reactors contributes to safe and efficient power generation, highlighting its significance in the complex landscape of nuclear energy.

As discussions surrounding clean energy intensify, the role of Cadmium in nuclear applications prompts a nuanced exploration of its benefits and challenges.

 

6. Cadmium in Electronics: Enhancing Conductivity


Cadmium finds application in electronics, where its alloys are employed to enhance the conductivity and solderability of components. Cadmium-based solders, often used in the assembly of electronic devices, ensure reliable connections and facilitate the seamless flow of electrical currents. While alternatives are being explored to mitigate environmental concerns, the historical relevance of Cadmium in electronics remains notable.

 

7. Responsible Usage and Environmental Considerations


Despite its widespread applications, the use of Cadmium has faced scrutiny due to its toxicity and environmental impact. Efforts to reduce Cadmium exposure in consumer products, especially in batteries and pigments, have led to the development of safer alternatives. The recycling of Cadmium-based products has also gained traction as a sustainable practice, minimizing the environmental footprint associated with this element.

 

Conclusion: Balancing Utility and Responsibility


Cadmium's journey through various industries reflects its undeniable utility alongside the ethical imperative of responsible usage. As technology and environmental awareness evolve, industries are navigating the delicate balance between harnessing the benefits of Cadmium and mitigating potential risks.

In the ever-changing landscape of innovation, the responsible utilization of Cadmium stands as a testament to the intricate interplay between scientific advancements, industrial needs, and environmental stewardship. As we forge ahead into a future defined by sustainability, the story of Cadmium serves as a reminder that progress must be achieved hand in hand with a commitment to ethical practices and environmental responsibility.

History

In the vast tapestry of chemical elements, Cadmium (Cd) emerges as a quietly resilient and versatile metal, its history intertwined with centuries of human discovery and industrial progress. From its unassuming origins to its pivotal role in modern technologies, the story of Cadmium is a fascinating journey that unveils the element's evolution and its impact on diverse aspects of human civilization.

 

1. The Elemental Dawn: Cadmium's Discovery and Isolation


Cadmium's historical narrative begins in the early 19th century when German chemist Friedrich Stromeyer made a serendipitous discovery. In 1817, while investigating the properties of zinc carbonate, Stromeyer identified a previously unknown substance that exhibited unique spectral lines. This marked the birth of Cadmium, named after the Latin word "cadmia" for calamine, the ore from which it was first isolated.

Stromeyer's meticulous work laid the foundation for understanding Cadmium's distinct characteristics and its eventual isolation as an independent element.

 

2. Artistic Brilliance: Cadmium in Pigments


Cadmium's radiant hues quickly caught the attention of artists in the late 19th and early 20th centuries. The element's incorporation into pigments led to the creation of Cadmium Yellow, Cadmium Red, and Cadmium Orange. Artists, including the likes of Vincent van Gogh, embraced these vibrant pigments, elevating the visual arts with a palette of colors that conveyed both intensity and subtlety.

Cadmium's influence on the art world reflected its ability to infuse creativity with a spectrum of brilliant tones, leaving an indelible mark on the canvases of masterpieces.

 

3. A Shimmering Alloy: Cadmium in Batteries


As the 20th century unfolded, Cadmium found a new realm of application in rechargeable batteries. The nickel-cadmium (NiCd) battery, developed in the early 1900s, became a workhorse in portable electronic devices. Cadmium's ability to form a stable electrode and facilitate reversible electrochemical reactions contributed to the efficiency and reliability of NiCd batteries, powering everything from early cameras to handheld gadgets.

While NiCd batteries have faced environmental concerns due to Cadmium's toxicity, their historical significance in portable power solutions remains undeniable.

 

4. The Nuclear Symphony: Cadmium in Control Rods


Cadmium's neutron-absorbing capabilities gained prominence in the mid-20th century in the field of nuclear energy. Control rods made from Cadmium or its alloys played a critical role in regulating nuclear reactions within reactors. By absorbing excess neutrons, these control rods allowed for precise control of the nuclear fission process, ensuring safety and efficiency in power generation.

Cadmium's contribution to nuclear technology reflects its adaptability to complex scientific challenges and its role in shaping the landscape of energy production.

 

5. Photovoltaic Harmony: Cadmium in Solar Cells


In the latter part of the 20th century, Cadmium's journey took an eco-friendly turn with its application in thin-film solar cells. Cadmium telluride (CdTe) solar panels emerged as an alternative to traditional silicon-based cells, offering cost-effectiveness and high conversion efficiency. The use of Cadmium in solar technology aligned with the growing emphasis on renewable energy sources, contributing to advancements in sustainable power solutions.

Cadmium's role in solar energy showcases its capacity to evolve with the changing tides of environmental consciousness and energy demands.

 

6. Present Challenges and Responsible Usage


While Cadmium's history is marked by valuable contributions to various industries, its toxicity has prompted a reassessment of its applications. Environmental and health concerns associated with Cadmium exposure have led to efforts to minimize its use, particularly in consumer products. The responsible management of Cadmium waste and recycling initiatives have become integral to mitigating its impact on ecosystems.

As industries navigate the challenges posed by Cadmium, the focus on responsible usage and sustainable practices becomes paramount.

 

Conclusion: Cadmium's Ongoing Symphony


The history of Cadmium is a testament to its resilience, adaptability, and profound impact on the human journey. From artists' palettes to nuclear reactors, from batteries to solar cells, Cadmium has woven itself into the fabric of progress, leaving a shimmering legacy that extends beyond its elemental confines.

As we traverse the present and gaze into the future, the story of Cadmium unfolds as a dynamic symphony of science, industry, and environmental consciousness. Balancing its rich history with responsible usage, Cadmium continues to play a role in the ongoing narrative of human ingenuity and the quest for sustainable solutions in the ever-evolving story of our world.

Atomic Data

Atomic Radiues, Non-bonded (A): 2.18
Electron Affinity (kJ mol-1): Not stable
Covalent Radiues (A): 1.40
Electronegativity (Pauling Scale): 1.69
Ionisation Energies (kJ mol-1) 1st 2nd 3rd 4th 5th 6th 7th 8th
867.772 1631.404 3616.27 - - - - -

Oxidation States and Isotopes

Common oxidation states 2
Isotope Atomic Mass Natural Abundance Half Life Mode of Decay
106Cd 105.906 1.25 > 1.9 x 1019 y EC, EC
108Cd 107.904 0.89 > 4.1 x 1017 y EC EC
110Cd 109.903 12.49 - -
111Cd 110.904 12.8 - -
112Cd 111.903 24.13 - -
113Cd 112.904 12.22 8.04 x 1015 y β-β-
114Cd 113.903 28.73 > 1.3 x 1018 y- β-β-
116Cd 115.905 7.49 3.8 x 1019 y β-β-
 

Supply Risk

Relative Supply Risk: 6.7
Crustal Abundance (ppm): 0.08
Recycle Rate (%): 10–30
Production Conc.(%) : 32
Top 3 Producers:
1) China
2) Republic of Korea
3) Japan
Top 3 Reserve Holders:
1) India
2) China
3) Australia
Substitutability: Low
Political Stability of Top Producer: 24.1
Political Stability of Top Reserve Holder: 10.8

Pressure and Temperature Data

Specific Heat Capacity: 231
Shear Modulus: 19.2
Young Modulus: 49.9
Bulk Modulus: 41.6
Pressure 400k Pressure 600k Pressure 800k Pressure 1000k Pressure 1200k Pressure 1400k Pressure 1600k Pressure 1800k Pressure 2000k Pressure 2200k Pressure 2400k
0.00028 18.2 - - - - - - - - 41.6

Podcast

Transcript :



Cadmium is a very versatile metal. It belongs the elements of Group 12 of the periodic table. It is designated as a chemical of very high concern due to its extreme toxicity. Some countries have introduced legislation to restrict the use of this element. Long-term exposure to this substance may cause cancer and renal impairment. It has been shown that a prolonged exposure to Cadmium leads to inflammation, which is the underlying mechanism of cardiovascular injury. This is the result of an imbalance of MMPs, which lead to cardiac fibrosis. Cadmium is now understood that the loss of structural integrity of cardiac tissue is observed by irregular branching patterns, complexed matrix networks, and focal areas of necrosis. These areas are marked by the presence of inflammatory cells.

On the other hand, Cadmium is harmful to both plants and animals. It is a heavy metal that is difficult to remove from area where it is present. Cadmium is commonly associated with lead, copper, and zinc. This is because it is generally combined with these elements to form compounds. There is no definite taste or odor for pure cadmium. Cadmium can be absorbed through cigarette smoke. If you smoke, you are more susceptible to Cadmium exposure than non-smokers.

Cadmium has a long history of isolation and discovery. It was first discovered in the mid-19th century by Friedrich Stromeyer and Karl Samuel. They found it in a mineral called zinc carbonate ore. The mineral, which is now known as stannite, contains 0.2% tin pyrite and 0.01-5% cadmium.

After the discovery of cadmium, other elements such as ruthenium, thulium, and gadolinium were discovered. These were also grouped together as transition metals.

Cadmium is naturally occurring; it is found in zinc ores in quantities of about one to two parts per million. It is also a byproduct of zinc production. Cadmium is present in a wide variety of different items. Since the medieval times, people have been aware of its existence. However, it is rarely found in nature. Humans have developed ways to produce and use concentrated sources of cadmium. The earth's crust contains less than one-fifth of a gram per ton. Typically, Cadmium is present in complex oxides and sulphides.

The greatest levels of cadmium are often detected in organ meats like liver and kidneys of animals. However, it is also found in other foods, such as seaweed and mushrooms.

Cadmium is found in many places around the world, but the largest producers of Cadmium are China, Japan, and Republic of Korea. Most rocks contain cadmium. Occasionally, it is released into the environment by forest fires or volcanoes. This element is present in various metals and nonferrous metals. In spite to this, it may also be created incidentally during some refining operations.

Cadmium, a bluish white metal. It is insoluble in water and is not flammable. however, in its powdered form it may burn and release toxic fumes. On the other hand, this metal is readily soluble in fuming nitric acid, but only slowly in hydrochloric and sulfuric acids and insoluble in basic solution.

The natural form of it, Cadmium sulfide, is widely studied for its semiconductor properties and is highly qualified in terms of its optical properties. The oxidation states of Cadmium are 0 and 4. It has a vapor pressure of about one millimeter of mercury at 394 degrees Celsius. At lower temperatures, it becomes ferromagnetic.

This element is used for industrial purposes such as in the manufacture of nuclear reactors and solar cells. Aside from its use in metallurgy, it is also used in nuclear reactors to control atomic fission. In addition, it is widely used in alloys. Cadmium is used in electrical batteries, solder, and pigments. This element is often used in electroplating and other devices. It is used in photodegradation, piezoelectronic devices and light-emitting diodes. It is used in a number of applications, including paints, high-quality plastics, and rechargeable nickel-Cadmium batteries. In the 1950s, Cadmium was widely used in yellow, orange, and red pigments. However, it was gradually withdrawn from the market due to health concerns.

References


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  • J. S. Coursey, D. J. Schwab, J. J. Tsai, and R. A. Dragoset, Atomic Weights and Isotopic Compositions (version 4.1), 2015, National Institute of Standards and Technology, Gaithersburg, MD, accessed November 2016.

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  • Thomas Jefferson National Accelerator Facility - Office of Science Education, It’s Elemental - The Periodic Table of Elements, accessed December 2014.