The actinide (/ ˈæktɪnaɪd /) or actinoid (/ ˈæktɪnɔɪd /) series encompasses the 15 metallic chemical elements with atomic numbers from 89 to 103, actinium
Actinium
Actinium is a chemical element with the symbol Ac and atomic number 89. It was first isolated by French chemist André-Louis Debierne in 1899. Friedrich Oskar Giesel later independently isolated it in 1902 and, unaware that it was already known, gave it the name emanium. Actinium gave the na…
Lawrencium
Lawrencium is a synthetic chemical element with the symbol Lr and atomic number 103. It is named in honor of Ernest Lawrence, inventor of the cyclotron, a device that was used to discover many artificial radioactive elements. A radioactive metal, lawrencium is the eleventh transuranic element and is also the final member of the actinide series. Like all elements with atomic number over 100, lawrencium c…
What are the two naturally occurring actinides?
The usual list of elements in the actinide series is:
- Actinium (Ac)
- Thorium (Th)
- Protactinium (Pa)
- Uranium (U)
- Neptunium (Np)
- Plutonium (Pu)
- Americium (Am)
- Curium (Cm)
- Berkelium (Bk)
- Californium (Cf)
What are the actinides in the periodic table of elements?
The usual list of elements in the actinide series is:
- Actinium (Ac)
- Thorium (Th)
- Protactinium (Pa)
- Uranium (U)
- Neptunium (Np)
- Plutonium (Pu)
- Americium (Am)
- Curium (Cm)
Are actinides metals nonmetals or metalloids?
The actinide series consists of elements 90-103, and these are named after the first member of the group actinium. They are radioactive and some are produced in laboratories. They are dense metals with high melting points.
What are the 12 elements of nature?
- bhūmi or pṛthvī ( earth ),
- āpas or jala ( water ),
- agní or tejas ( fire ),
- vāyu, vyāna, or vāta ( air or wind)
- ākāśa, vyom, or śūnya (space or zero) or ( aether or void ).
What are Actinides?
The term ‘ actinide series’ has been derived from the first element of the series, actinium. The symbol An is used while referring to any of the actinide series elements which range in the periodic table from atomic numbers 89 to 103.
Why are actinides electropositive?
Because of the lower ionization energy, actinides are electropositive than lanthanides and most reactive. They react with hot water. React with oxidizing agents and form a passive coating. Form halides and hydrides. Actinides are strong reducing agents.
Why do actinides have lower enthalpies than lanthanides?
The actinides have lower ionization enthalpies than lanthanides because 5f electrons are more effectively shielded from nuclear charge than 4f.
Why do tri positive actinides decrease in size?
The atomic size/ ionic radii of tri positive actinides ions decrease steadily from Th to Lw due to increasing nuclear charge and electrons entering the inner (n-2) f orbital.
What are the magnetic properties of actinides?
Magnetic Properties of Actinides: All actinides are paramagnetic in nature, which depends on the presence of unpaired electrons. The orbital angular moment is quenched because of the shielding of 5f electrons so that the observed magnetic moment is less than the calculated. Test your Knowledge on actinides. Q 5.
What are the elements that are radioactive?
Actinides are elements with atomic numbers from 90 to 103 following element Actinium. They include naturally occurring elements of thorium, protactinium and uranium and eleven transuranic i.e., artificially produced by nuclear reactions. Nevertheless, all actinides are radioactive.
What is the electronic configuration of actinides?
The general electronic configuration of actinides is [Rn] 5f1-14 6d0-1 7s2. Here [Rn] is the electronic configuration of the nearest noble gas which is Radium.
What are the elements in the actinides group?
The actinides group includes mostly man-made elements with only a few exceptions such as uranium and thorium. The actinides are most known for the elements uranium and plutonium which are used in nuclear reactors and nuclear bombs. The lanthanides and actinides are located mostly in the "f-block" of the periodic table.
Where are lanthanides and actinides located?
The lanthanides and actinides are located mostly in the "f-block" of the periodic table. Lanthanides are used in products such as hybrid cars, superconductors, and permanent magnets. The actinide americium is used in smoke detectors.
What are the elements that are often called the inner transition metals?
They are often called the "inner transition metals.". The lanthanides are the elements with atomic numbers from 57 to 71. These 15 metals (along with scandium and yttrium) are often called the rare earth elements. They are all silvery-white metals which are often found in the same ores.
How many elements are in the lanthanides and actinides?
They are the elements that are often listed below the main section of the periodic table. There are thirty total elements in the lanthanides and actinides. They are often called the "inner transition metals."
Why are lanthanides called lanthanides?
They are called the lanthanides because they exhibit similar chemical properties to lanthanum, the first element in the group. Actinides are the 15 elements with atomic numbers from 89 to 103. They are named after the first element in the series, actinium.
Is lanthanide radioactive?
The name "actinium" comes from the Greek word "aktis" which means beam or ray. Both actinides and lanthanides are highly reactive with elements from the halogen group. All of the lanthanides have at least one stable isotope except for promethium. None of the actinides have a stable isotope. They are all radioactive.
