Actinium

Extracted Attributes

• Appearance

  Soft, silvery-white metal that glows with a pale blue light in the dark due to intense radioactivity

• Key Isotopes

  Ac-225, Ac-227, Ac-228

• Atomic Number

  89

• Chemical Symbol

  Ac

• Element Category

  Actinide

• Primary Applications

  Radiation therapy (targeted alpha therapy for cancer), neutron source, and scientific research

Timeline

• Actinium is discovered by French chemist André-Louis Debierne. (Source: Wikipedia)

  1899-01-01

• Friedrich Oskar Giesel independently discovers the element and names it emanium. (Source: Wikipedia)

  1902-01-01

Actinium

Actinium is a chemical element; it has symbol Ac and atomic number 89. It was discovered by Friedrich Oskar Giesel in 1902, who gave it the name emanium; the element got its name by being wrongly identified with a substance André-Louis Debierne found in 1899 and called actinium. The actinide series, a set of 15 elements between actinium and lawrencium in the periodic table, is named after actinium. Together with polonium, radium, and radon, actinium was one of the first non-primordial radioactive elements to be discovered. A soft, silvery-white radioactive metal, actinium reacts rapidly with oxygen and moisture in air, forming a white coating of actinium oxide that prevents further oxidation. As with most lanthanides and many actinides, actinium assumes oxidation state +3 in nearly all its chemical compounds. Actinium is found only in traces in uranium and thorium ores as the isotope 227Ac, which decays with a half-life of 21.772 years, predominantly emitting beta and sometimes alpha particles, and 228Ac, which is beta active with a half-life of 6.15 hours. One tonne of natural uranium in ore contains about 0.2 milligrams of actinium-227, and one tonne of thorium contains about 5 nanograms of actinium-228. The close similarity of physical and chemical properties of actinium and lanthanum makes the separation of actinium from the ore impractical. Instead, the element is prepared, in milligram amounts, by the neutron irradiation of 226Ra in a nuclear reactor. Owing to its scarcity, high price, and radioactivity, actinium has no significant industrial use. Its current applications include a neutron source and an agent for radiation therapy.

Web Search Results

• Actinium - Wikipedia

  Actinium is a chemical element; it has symbol Ac and atomic number 89. It was discovered by Friedrich Oskar Giesel in 1902, who gave it the name emanium; the element got its name by being wrongly identified with a substance André-Louis Debierne found in 1899 and called actinium. The actinide series, a set of 15 elements between actinium and lawrencium in the periodic table, is named after actinium. Together with polonium, radium, and radon, actinium was one of the first non-primordial radioactive elements to be discovered. [...] ## Properties Actinium is a soft, silvery-white, radioactive, metallic element. Its estimated shear modulus is similar to that of lead. Owing to its strong radioactivity, actinium glows in the dark with a pale blue light, which originates from the surrounding air ionized by the emitted energetic particles. Actinium has similar chemical properties to lanthanum and other lanthanides, and therefore these elements are difficult to separate when extracting from uranium ores. Solvent extraction and ion chromatography are commonly used for the separation. [...] A soft, silvery-white radioactive metal, actinium reacts rapidly with oxygen and moisture in air, forming a white coating of actinium oxide that prevents further oxidation. As with most lanthanides and many actinides, actinium assumes oxidation state +3 in nearly all its chemical compounds. Actinium is found only in traces in uranium and thorium ores as the isotope 227Ac, which decays with a half-life of 21.772 years, predominantly emitting beta and sometimes alpha particles, and 228Ac, which is beta active with a half-life of 6.15 hours. One tonne of natural uranium in ore contains about 0.2 milligrams of actinium-227, and one tonne of thorium contains about 5 nanograms of actinium-228. The close similarity of physical and chemical properties of actinium and lanthanum makes the

• Actinium (Ac) | Science | Research Starters | EBSCO Research

  # Actinium (Ac) Actinium (Ac) is a naturally occurring radioactive element with the atomic number 89 and a relative atomic weight of 227. It belongs to the actinide series, which includes elements with atomic numbers ranging from 89 to 103, and is located in Group 3b of the periodic table. Discovered in 1899 by French chemist André-Louis Debierne, actinium is found in minute quantities within uranium ores, making laboratory production a more feasible method for obtaining this element. Notably, actinium is characterized by its silvery-white appearance and a luminescent blue glow, which is a result of its radioactive properties. [...] ## On This Page ## Full Article ### Actinium (Ac) Actinium is a naturally occurring radioactive element with the chemical symbol Ac. Its atomic number is 89, and its relative atomic weight is 227. Its electronic configuration is [Rn] 6d17s2. In the periodic table, it is placed in Group 3b, within period 7, and it falls between the elements radium and thorium. Actinium is placed in a group of elements called the actinides. These elements are assigned atomic numbers from 89 to 103, and their chemical properties are similar to each other, but they differ from other elements in the periodic table. [...] ## Full Article ### Actinium (Ac) Actinium is a naturally occurring radioactive element with the chemical symbol Ac. Its atomic number is 89, and its relative atomic weight is 227. Its electronic configuration is [Rn] 6d17s2. In the periodic table, it is placed in Group 3b, within period 7, and it falls between the elements radium and thorium. Actinium is placed in a group of elements called the actinides. These elements are assigned atomic numbers from 89 to 103, and their chemical properties are similar to each other, but they differ from other elements in the periodic table.

• Actinium Suppliers | AMERICAN ELEMENTS®

  Actinium Bohr Model Actinium is an F-Block, Period 7 element. The number of electrons in each of Actinium's shells is 2,8,18,32,18,9,2 and its electron configuration is [Rn] 6d1 7s2. Actinium The actinium atom has a radius of 195 pm. In its elemental form, CAS 7440-34-8, actinium has a silvery-white appearance. Actinium is a radioactive metal that rapidly reacts rapidly with oxygen when exposed to air, forming a white coating of actinium oxide which prevents further oxidation. Actinium is found naturally in uranium ores. It rarely occurs as a free element in the earth’s crust. It is more frequently produced in the lab, largely for use as a radiation source. Actinium was first noted as a new element by a French chemist, André-Louis Debierne, in 1899. It was discovered again as an [...] 简化字 Deutsch español français हिन्दी italiano 日本語 한국어 nederlands português России svensk English American Element site logo Cart 0 Your shopping cart is empty! EXPLORE MATERIALS SCIENCE TOOLBOX ## Actinium 89 Ac 227 # Actinium Suppliers to the World About Actinium Products Properties Properties & Products Safety Isotopes ## About Actinium Actinium, a silver-white metallic element, is the namesake of the actinides group in the periodic table, a series of elements known for their radioactivity. Due to its radioactive nature and relative scarcity on Earth, actinium has not historically enjoyed many commercial or industrial uses or applications; however, that may be changing with ongoing scientific research into both medicine and spacecraft power systems. [...] Actinium information, including properties, research, applications and other useful facts are discussed below. Scientific facts such as the atomic structure, ionization energy, abundance on Earth, conductivity and thermal properties are included. #### General Properties | | | --- | | Symbol: | Ac | | Atomic Number: | 89 | | Atomic Weight: | 227 | | Element Category: | Actinide | | Group, Period, Block: | n/a, 7, f | | Color: | silvery white | | Other Names: | Attinio | #### Physical Properties

• Actinium: Element Properties and Uses

  Voice ## Description Actinium is a highly radioactive, silvery-white metal with the atomic number 89. This intensely reactive metal produces a faint blue light due to its radioactivity, and is applied in a very specialized way in neutron sources and scientific research and emerging cancer treatments. It is still an extremely rare element and challenging to purify in its absolute form. Introduction to the Element [...] Introduction to the Element Actinium is a naturally occurring radioactive substance and the first member of the actinide series. It was discovered in the late 19th century and appears to be a soft, silvery metal which tarnishes right away if exposed to air. Actinium looks like a typical lanthanide chemically, particularly favoring the +3 oxidation state. Although it looks like a metal, the substance is actually highly reactive since it constantly undergoes radioactive decay and easily oxidizes. ## History and Development [...] ## History and Development Actinium was independently discovered by André-Louis Debierne in 1899 and by Friedrich Oskar Giesel in 1902. Its identity and classification were initially a matter of scientific controversy, but continued research established it to be the first element of the actinide series. Over the years, nuclear science development, especially the technology of reactors and radiotherapy, expanded interest in actinium. The discovery of the isotope Ac-225 opened new pathways in targeted alpha therapy (TAT), a promising cancer treatment that uses focused alpha radiation to damage tumor cells while minimizing effects on surrounding tissues.

• About :: Actinium Pharmaceuticals, Inc. (ATNM)

  Actinium is a pioneer in the development of differentiated targeted radiotherapies intended to meaningfully improve patient outcomes. ATNM-400, Actinium's lead product candidate, is a novel, first-in-class, and multi-indication Actinium-225 (Ac-225) in development for prostate cancer, non-small cell lung cancer (NSCLC) and breast cancer. The antigen specifically targeted by ATNM-400 is highly expressed in metastatic castration-resistant prostate cancer (mCRPC), contributes directly to disease progression, poorer survival outcomes, and continues to be expressed at a high level even after androgen receptor inhibitor (ARPI) and Pluvicto® treatment. ATNM-400 is supported by preclinical data demonstrating tumor-specific uptake, higher efficacy than androgen receptor inhibitor enzalutamide [...] checkpoint inhibitors including KEYTRUDA® and OPDIVO® by depleting myeloid derived suppressor cells (MDSCs), which represents a potential multi-billion-dollar addressable market. Iomab-ACT, Actinium's next generation conditioning candidate, is being developed with the goal of improving patient access and outcomes for potentially curative cell and gene therapies. Iomab-B is an induction and conditioning agent prior to bone marrow transplant in patients with r/r AML, which Actinium is seeking a potential strategic partner for the U.S. In addition, the company's R&D efforts are primarily focused on advancing several preclinical programs for solid tumor indications. Actinium holds approximately 250 patents and patent applications including several patents related to the manufacture of the