Did you know that rhodium is more precious than gold? Rhodium, however, is occasionally used to plate fake jewelry made of less expensive metals even though it is more expensive than other precious metals. Rhodium is less likely to tarnish than other plating metals. Rhodium does, however, have specific additional unique properties. Is rhodium magnetic?
In this article, we answer that question. We will also describe rhodium and discuss its radioactivity, waterproofness, and cost. We conclude by highlighting the properties and uses of rhodium.
What is Rhodium?
Rhodium is a metallic element with a silvery white color and excellent reflectivity. Aside from being one of the six PGM metals (platinum, iridium, osmium, palladium, ruthenium), it is regarded as one of the rarest and most expensive metals globally. Along with other platinum metals, it occurs in nature in its purest form.
It is extracted as a by-product of platinum, palladium, and nickel mining. Over 85% of the world’s rhodium is produced in South Africa. In North and South America, river sands naturally contain rhodium. Additionally found in the Canadian province of Ontario’s copper-nickel sulfide ores. Rhodium is also abundant in the Russian Ural Mountains.
Will Rhodium Stick to a Magnet?
Rhodium will stick to a magnet. It is a metallic paramagnetic material. Rhodium is hence very lightly attracted to a strong magnetic field. The ability of rhodium to interact weakly with a magnetic field is due to the existence of unpaired electrons in its atomic structure. Rhodium, however, loses its magnetic properties when you remove the magnetic field.
Rhodium’s valence electrons are not grouped in any specific sequence and do not favor any particular spin direction.
But interestingly, rhodium behaves as though it has a general magnetic moment, even though there is no preferred direction for the spin. The magnetic moments of the electrons in each atom line up to cause this effect. Differentiating it from ferromagnetic metals, like nickel, which have an intrinsic magnetic moment.
Despite this weak connection, rhodium’s paramagnetic principles are still relevant. Rhodium is applied on hard disk drives as a protective coating in some applications, like magnetic data storage. However, a strong magnetic field’s behavior toward rhodium will depend on several variables, including temperature and impurities.
Is Rhodium Radioactive?
There is only one non-radioactive naturally occurring isotope of rhodium. However, rhodium also contains 25 radioactive isotopes. 18 have half-lives under one hour. The half-life of the remainder is 2.9 years. It implies that rhodium’s radioactivity diminishes after every hour or 2.9 years. These are often artificially produced isotopes that decompose into other elements very quickly.
Radioactivity indicates that a substance’s atomic nucleus is unstable and trying to move to a more stable state by releasing some energy. The atoms can discharge “energy” in one of three ways to become stable:
- Emission of alpha particles: Alpha particles are released by atomic nuclei. Two protons and two electrons are tightly bound to form an alpha particle. Usually released during alpha decay.
- Conversion of protons to neutrons or vice versa: In the nucleus, a proton can change into a neutron and vice versa. Beta decay is the name of the process. When the proton is converted to a neutron, it is known as β+ decay. When a neutron is converted to a proton, it is known as a β– decay. A beta particle releases as a result of the nucleus changing.
- Spontaneous fission: The nucleus divides into two equal fragments and numerous free neutrons during this radioactive decay. There is a significant energy release. Stray neutrons can prematurely trigger a chain reaction. However, atomic nuclei with an atomic number of 90 experience spontaneous fission. Since rhodium has an atomic number of 45, the process is unsuccessful.
Is Rhodium Waterproof?
Rhodium is waterproof. It is corrosion-resistant and does not discolor or rust. Rhodium does not react with pure water. Rhodium will, however, lose its shine more quickly if it is exposed to water. Water also affects rhodium when the temperature reaches 1112°F (600°C). It’s best to remove your jewelry when swimming because chemicals in pools react with rhodium.
Rhodium is often used for plating because it is waterproof. Rhodium plating gives jewelry a smooth, lustrous finish while enhancing the brilliance and toughness of metals like silver and platinum. However, the jewelry will get discolored if the rhodium plating is too thin.
Does this imply you don’t have to remove your rhodium-plated jewelry while showering? As soap and shampoos contain chemicals that can readily react with rhodium, it is not a smart idea. Your aftershave, sprays, and fragrances will also affect rhodium in time and water.
Is Rhodium Expensive?
Rhodium is an expensive metal. Because of the decline in production, its prices are still rising. At this time, an ounce costs $10,000. It is rare because it does not exist as a single mineral. Rhodium is expensive because of its high demand and limited supply. The cost, though, is subject to change. It is, therefore, not a noble investment.
Rhodium hit a record-high price of $ 29,800 per ounce in March 2021. The troy ounce is used to quantify extremely precious materials like platinum and rhodium. It’s expensive compared to other PDMs due to its intricate industrial extraction method. Therefore, rising demand and a limited supply have increased rhodium prices.
Only one significant supplier exists in South Africa. The South African rhodium mining industry is dealing with serious problems that impact its mining operations, making rhodium even more scarce.
However, increased mining of palladium, a substitute for rhodium, could eventually lead to a drop in price and demand. However, rhodium prices are still skyrocketing until then.
Properties of Rhodium
The atomic number of rhodium is 45, and its symbol is Rh. Rhodium is a noble metal that belongs to the PGM family and is chemically inert. It can be found in other metal ores or as a free metal.
The table below highlights further rhodium properties.
|-Boils at a peak temperature of 6687°F (3697°C).
|-Hard, shiny, silvery metal.
|-The melting boiling point is 3567 °F (1964 °C).
|-Adding specific inks creates color variations.
|-Atomic mass 102.9055 u and atomic number 45.
|-Does not tarnish nor corrode.
|-Belongs to the periodic table’s group 9’s period 5 category.
|-Contains 47 neutrons and 45 electrons.
|-Durable due to harness and strength.
|-It doesn’t react with most acids, air, or water under normal circumstances.
|-Brittle and does not bend easily.
Uses of Rhodium
In 1803 by Willian Hyde Wollaston, rhodium was discovered. The word “rhodon” in Greek, which means “rose-colored,” is the origin of the word’s name. It has grown in prominence across several industries. We discuss its primary functions.
- The main application is in gasoline-powered cars’ catalytic converters, which assist lower the amount of nitrogen oxides released into the atmosphere. A catalytic converter is used in vehicles to convert unburned nitrogen oxide, carbon monoxide, and other hydrocarbons into less harmful gases. The emissions can then release without causing any environmental harm to the atmosphere.
- Rhodium acts as a catalyst in the production of acetic, nitric, and hydrogenation processes in the chemical industry. Rhodium-containing catalysts aid in the manufacture of the basic ingredients needed to make fertilizers and explosives.
- Its a glass strengthening alloy. It has the perfect characteristics for creating the vessels that contain and shape molten glass. Used to produce liquid crystals display(LCDS) and glass fiber.
- Rhodium can be used as a protective coating on jewelry pieces to protect from scratches and tarnishes. It can be electroplated onto gold and platinum to give the jewelry a shiny appearance and feel. Rhodium can also be used to coat sterling silver to prevent tarnishing. Due to its scarcity and high cost, rhodium is primarily used as a coating agent rather than a solid metal.ue to its rarity and high price.
- It’s interesting to note that rhodium is often used in prices and medals to signify honors. The Guiness Book of World Records presented a rhodium-plated vinyl to the well-known musician and songwriter Paul McCartney (one of the founding members of the Beatles) in 1979.
- It is also used to coat optic fibres, and optic mirrors.
- Used as an alloying agent to improve and harden platinum and palladium’s corrosion resistance. The alloys are used to create thermocouple elements, electrodes for aviation spark plugs, headlamp reflectors, and laboratory crucibles.
- Electrical contacts, printed circuit boards (PCBs), semi-conductor wafers, and other mission-critical components use rhodium as an electrical contact. That is made possible by its strong corrosion resistance and low electrical resistance.
- Because of the characteristics X-rays it produces rhodium is used as filters in mammography systems. Rhodium helps to produce a more penetrating X-ray beam than the standard molybdenum anode. Some mammogram systems have a dual track ( rhodium+ molybdenum) X-ray tube anode.
Due to its paramagnetic nature, rhodium adheres to magnets. Rhodium has unpaired electrons in its atomic structure, but it tends to lose its magnetic properties when the magnetic field is removed.
It has 25 artificial radioactive isotopes and is a PGM member. Rhodium is one of the most expensive metals because of its complex extraction method and constrained availability.