Americium: Properties, Isotopes, and Uses

From the discovery of ‘Glenn Seaborg’ and colleagues, Americium (Am) with its atomic number 95, is known for 2 key things: Absence of Isotopes and regarded as an actinide which is made-made. From being a substitute to Plutonium in 1 area to acting as a decay product in another, Americium uses are only a few but important ones.  Possessing certain physical and chemical properties quite different from the rest of its actinide elements, we are about to learn about the Definition, properties, some interesting facts and Americium (Am) uses with a detailed overview. 

Basic Things to Know about Americium

Americium is an actinide created by humans and is located in the 7th row in the f-block of the periodic table. There are a total of 15 actinide elements in the periodic table and Americium (Am) is 1 among the group, starting with Actinium. The credits for the discovery goes to the research members from the “University of California” namely Glenn Seaborg, Albert Ghiorso, Ralph James, and Leon Morgan, at a major site assigned by the US Government for wartime resource development. 

Moreover, the naming itself has an interesting fact associated with it. ‘Americium’ was the term labelled for this man-made chemical element in the stance of giving honours to the American Continent. This nomenclature was specifically chosen since this newly created compound is present below the Europium (that is Europe) in the periodic chart.

The element was found in 1944 as the by-product in military research during the times of World War II (1939-45). This was then isolated in the Fall of 1945 by B.B. Cunningham. The isolated component is termed isotope 241Am with Am(OH)3. 

As we now grasped the basic details about Americium (Am), let us move further to the important sections of properties. 

The Physical Properties of Americium 

• White-coloured Silvery metal.

• Sufficient amounts of Americium element was needed to at least study the details about its main properties.

• Present as solid at 20°C.

• The Pronunciation of this element is [am-uh-REE-see-um].

• Only 1 isotope is noted to have applications outside a clinical laboratory.

• Americium belongs to the Transuranium (the literal meaning is “beyond uranium” and the atomic number should be more than 92) elements. 

• It is not probable to find Transuranium chemical compounds in the natural environment. They are majorly formed using synthetic materials and processes only. So, the extraction of Americium is absent here.

Listing out Americium’s Chemical Properties 

• The symbol is [Am].

• The atomic number is 95. 

• [Rn] 5f77s2 is the Electronic Configuration. 

• 2011°C at 3652°F with a temperature of 2284 K is the boiling point of Am.

• The melting point is 1,175°C at 2,150°F.

• 13.6 grams per cubic centimetre is the density of Americium. 

• The Relative Atomic Mass is found to be 243.0614 g.mol -1.

A Gist About the Isotopes of Americium

Every isotope of Americium is said to be highly radioactive, out of which, americium-241 is the most resolute one. It is estimated that 432.7 years is the approximate half-life of americium-241. 

That is if a clinic has created 9.4 grams of americium-241, then by the end of 432.7 years, the next set of people will witness only half the amount present in its compound. The remaining half will be converted into a new chemical element. 

Real-Life Americium Uses

As we read before, only 1 isotope, that is ‘Am-241’ has practical Americium uses outside the clinical setup. Since both alpha and gamma rays are exhibited from this isotope, it makes americium-241 possible to use it in portable X-ray machines. This also has practical usages in the field of underground mining and oil well drilling since it helps in finding the location as to where to dig the new wells. 

For newly made glass materials, a minimal amount of Americium can be placed over the conveyor belt carrying the object. So, the Geiger counter is used to count the alpha radiation-exposed is kept below the belt on the line. By doing this, measuring the thickness of specific things and entities is possible. 3 interpretations are possible using americium-241 and the Geiger counter as given below: 

1. If the radiation is less detected, then the glass object is thicker than usual. 

2. If the radiation is more, the glass is quite thinner than regular ones.

3. If the glass material is of the usual or same thickness, then the trapped radiation and the thickness of the object will both be equal when observed from the detector. 

In the production of spacecraft batteries, Americium is the key substitute when Plutonium is absent or minimally available. 

Americium is even found in household ionization smoke-detectors. The element takes an important role inside smoke detectors, in the combination of americium oxide and americium-241. Alpha particles created here will strike the air molecules and thus, makes them break and form electrically-charged ionic particles. These entities are carrying current from 1 side to another and the electricity is passed as long as the presence of air. The buzzer sound comes out only if the alpha charges interrupt the flow of electrical ions. 

• As an interesting add-on to the stated, having as low as 1 gram of the combination of Americium Oxide and americium-241, can be effective in manufacturing 5000 different smoke detectors!

Americium is also used as a decay product in several nuclear power production systems. 

On a precautionary side, Americium is a highly toxic substance. Swallowing Americium even accidentally will lead to the deposition of this element in the human bones. Radiation spread from here kills the body’s healthy cells and triggers issues such as cancer and other major forms of melanoma. However, smoke detectors using Americium is not a crucial danger to humans.

Conclusion 

Americium is a man-made silver, shiny, chemical compound, classified under the transuranium elements and actinides in the f-block of the periodic table. Located in the 7th row, Americium’s atomic number is 95 and is not found naturally in the surrounding environment. B.B. Cunningham isolated the element and was discovered by Glenn Seaborg with 4 other research members during World War II. Americium was named for the element to denote the continent of America, lying below the Europium in the periodic table. Americium has only 1 major isotope, americium-214 that has a good number of applications beyond a lab. Replacement for spacecraft batteries, ionization smoke detectors, Decay product for nuclear reactors.