Actinium: Discovery, Electronic Configuration, Properties, Uses, Effects

In the actinide series, actinium is the first and most important element. The chemical element actinium has the atomic number 89 and the symbol Ac. Actinium is radioactive in all 36 of its known isotopes. Ac 227 and Ac 228 are naturally occurring isotopes that are 150 times more radioactive than radium and have half-lives of 21.77 years and 6.13 hours, respectively. Health-wise, it is dangerous. The radioactive decay of the substance causes cell damage if it is swallowed, it gets accumulated in the bones and liver of humans.

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This Story also Contains

1. Discovery Of Actinium
2. Electronic Configuration Of Actinium
3. Physical Properties Of Actinium
4. Chemical Properties
5. Occurrences
6. Uses Of Actinium
7. Effects Of Actinium On Health
8. Effects Of Actinium On The Environment

Discovery Of Actinium

Actinium is derived from the Greek words aktis and aktinos, which imply beam and ray, respectively. In 1899, French chemist André-Louis Debierne declared the discovery of this new element. After Marie and Pierre Curie removed radium, they left behind pitchblende leftovers, which he separated from them. The element was initially discovered in 1902 and given the name “emanium” by Friedrich Oskar Giesel. A set of 15 related elements in the periodic table between actinium and lawrencium were first referred to as the actinide series after the element actinium. Actinium was one of the first radioactive elements discovered outside of the original nucleus, along with polonium, radium, and radon.

Electronic Configuration Of Actinium

The ground-state electron configuration of ground-state gaseous neutral actinium is given as follows:

• Short-hand electronic configuration: [Rn] 6d¹ 7s²

• Electronic Configuration: 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d¹⁰10 6s² 6p⁶ 6d¹ 7s²

• The shell structure of actinium atoms, which have 89 electrons, has electrons per Shell as: 2, 8, 18, 32, 18, 9, 2.

Physical Properties Of Actinium

• Actinium is a soft, silvery-white radioactive metal.

• Actinium has a bright radioactive glow that is visible in the dark and is caused by the air around it being ionised by the emitted energetic particles.

• Actinium oxide is a white coating-like substance that is created when this radioactive element and oxygen react.

• When maintained in a solution, the actinium ions are colourless.

Chemical Properties

• Due to their similar chemical makeup, actinium and other lanthanides are challenging to distinguish when extracted from uranium ores.

• Actinium takes an oxidation state of +3 in almost all of its chemical compounds, much like the majority of lanthanides and many actinides do.

• They combine quickly with oxygen and moisture in the air to produce a layer of actinium oxide that shields it from further oxidation.

Occurrences

• Only trace amounts of actinium are found in the ores of uranium and thorium as the beta-active isotopes 228Ac and 227Ac,

• The isotope 227Ac decays with a half-life of 21.772 years and primarily emits beta and occasionally alpha particles

• The other isotope 228Ac, which is beta active and has a half-life of 6.15 hours, are the only traces of actinium that can be detected in uranium and thorium ores.

• Actinium-227 makes up around 0.2 milligrams of one tonne of natural uranium in ore, while Actinium-228 makes up roughly 5 nanograms of one tonne of thorium.

Uses Of Actinium

• It is useful as a neutron source since it is around 150 times more radioactive than radium. It doesn't have any substantial industrial applications except that.

• It is an essential source of alpha rays. Ac 225 is a radiation therapy agent that is employed in the medical field.

• The radioactive isotope 227Ac is a very useful one for modelling the gradual vertical mixing of ocean waters due to its medium half-life of 21.77 years.

• In medicine, actinium-225 is used to make Bi-213 in a reusable generator or as a single agent for radio-immunotherapy.

Effects Of Actinium On Health

• Due to its high radiation hazard, actinium-227 is about as harmful as plutonium in terms of potential health impacts from radiation exposure. Actinium-227 would pose a major health risk even if very tiny doses were consumed.

• Radiation damage to the gene pool, or the genetic makeup of all living species, is the biggest danger to life as we know it. Over a person's lifetime and subsequent generations, radiation exposure causes cumulative genetic harm.

• Once exposed for a long time, even low-dose exposures become carcinogenic. Cancers, immune system damage, leukaemia, miscarriages, stillbirths, abnormalities, and fertility issues could affect the current generation, the one that will soon be born, and all subsequent generations.

• Despite the fact that a lot of these health issues are getting worse, no one can definitively attribute the growth in "background" radiation or a particular dose to the difficulties.

• Science only permits the imputation of causality based on epidemiological evidence. The ability to reproduce would just completely disappear, which might be the most extreme result over time. Sterility can be brought on by radiation.

Effects Of Actinium On The Environment

The advancement of nuclear technology has been followed by massive as well as minute releases of radioactivity into the atmosphere, the land, the oceans, seas, and water table, manifesting itself everywhere in living things like plants, animals, and inert matter. Other animals and people are exposed to the harmful effects of radiation as it spreads across species and accumulates up the food chain.

Extremely radioactive actinium-227 is used. All living things are affected by radioactivity's damage to the gene pool, which results in malignancies, immune system disorders, leukaemia, miscarriages, stillbirths, abnormalities, and issues with fertility in addition to harming human beings. Additionally, radiation exposure causes genetic harm that accumulates over a person's lifetime and over several generations.