Actinides

Group of 15 chemical elements

The actinides are a series of 15 chemical elements in the periodic table with atomic numbers from 89 to 103, from actinium through lawrencium. These elements are all f-block elements, with the exception of actinium, which is a d-block element. The actinides are known for their radioactive properties and are typically found in the actinide series of the periodic table.

Properties[edit | edit source]

The actinides are characterized by their ability to form multiple oxidation states, typically ranging from +3 to +6. They are all radioactive, with some having very long half-lives, such as uranium-238, while others, like lawrencium, have very short half-lives. The actinides are typically metallic and have high densities and high atomic and ionic sizes.

The chemistry of the actinides is dominated by the presence of the 5f electrons, which are less tightly bound than the 4f electrons in the lanthanides. This results in a greater degree of covalency in the actinide compounds compared to the lanthanide compounds.

Occurrence[edit | edit source]

The actinides are not as abundant as the lanthanides. Uranium and thorium are the most abundant actinides in the Earth's crust and are used as fuel in nuclear reactors. Plutonium is another significant actinide, primarily produced in nuclear reactors from uranium-238.

Applications[edit | edit source]

Actinides have several important applications, particularly in the field of nuclear energy. Uranium and plutonium are used as fuel in nuclear reactors and in the production of nuclear weapons. Thorium is being researched as a potential alternative nuclear fuel due to its abundance and potential for producing less nuclear waste.

Health and Safety[edit | edit source]

Due to their radioactivity, actinides pose significant health risks. Exposure to actinides can lead to radiation poisoning and increase the risk of cancer. Proper handling and disposal of actinide materials are crucial to minimize these risks.

List of Actinides[edit | edit source]

The actinide series includes the following elements:

Actinium (Ac)
Thorium (Th)
Protactinium (Pa)
Uranium (U)
Neptunium (Np)
Plutonium (Pu)
Americium (Am)
Curium (Cm)
Berkelium (Bk)
Californium (Cf)
Einsteinium (Es)
Fermium (Fm)
Mendelevium (Md)
Nobelium (No)
Lawrencium (Lr)

Also see[edit | edit source]

Group	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18
	Hydrogen & alkali metals	Alkaline earth metals											Triels	Tetrels	Pnictogens	Chalcogens	Halogens	Noble gases
Period 1	[[ hydrogen \|Hydrogen1H1.0080]]																	[[ helium \|Helium2He4.0026]]
2	[[ lithium \|Lithium3Li6.94]]	[[ beryllium \|Beryllium4Be9.0122]]											[[ boron \|Boron5B10.81]]	[[ carbon \|Carbon6C12.011]]	[[ nitrogen \|Nitrogen7N14.007]]	[[ oxygen \|Oxygen8O15.999]]	[[ fluorine \|Fluorine9F18.998]]	[[ neon \|Neon10Ne20.180]]
3	[[ sodium \|Sodium11Na22.990]]	[[ magnesium \|Magnesium12Mg24.305]]											[[ aluminium \|Aluminium13Al26.982]]	[[ silicon \|Silicon14Si28.085]]	[[ phosphorus\|Phosphorus15P30.974]]	[[ sulfur \|Sulfur16S32.06]]	[[ chlorine \|Chlorine17Cl35.45]]	[[ argon \|Argon18Ar39.95]]
4	[[ potassium \|Potassium19K39.098]]	[[ calcium \|Calcium20Ca40.078]]	[[ scandium \|Scandium21Sc44.956]]	[[ titanium \|Titanium22Ti47.867]]	[[ vanadium \|Vanadium23V50.942]]	[[ chromium \|Chromium24Cr51.996]]	[[ manganese \|Manganese25Mn54.938]]	[[ iron \|Iron26Fe55.845]]	[[ cobalt \|Cobalt27Co58.933]]	[[ nickel \|Nickel28Ni58.693]]	[[ copper \|Copper29Cu63.546]]	[[ zinc \|Zinc30Zn65.38]]	[[ gallium \|Gallium31Ga69.723]]	[[ germanium \|Germanium32Ge72.630]]	[[ arsenic \|Arsenic33As74.922]]	[[ selenium \|Selenium34Se78.971]]	[[ bromine \|Bromine35Br79.904]]	[[ krypton \|Krypton36Kr83.798]]
5	[[ rubidium \|Rubidium37Rb85.468]]	[[ strontium \|Strontium38Sr87.62]]	[[ yttrium \|Yttrium39Y88.906]]	[[ zirconium \|Zirconium40Zr91.224]]	[[ niobium \|Niobium41Nb92.906]]	[[ molybdenum\|Molybdenum42Mo95.95]]	[[ technetium\|Technetium43Tc[97]]]	[[ ruthenium \|Ruthenium44Ru101.07]]	[[ rhodium \|Rhodium45Rh102.91]]	[[ palladium \|Palladium46Pd106.42]]	[[ silver \|Silver47Ag107.87]]	[[ cadmium \|Cadmium48Cd112.41]]	[[ indium \|Indium49In114.82]]	[[ tin \|Tin50Sn118.71]]	[[ antimony \|Antimony51Sb121.76]]	[[ tellurium \|Tellurium52Te127.60]]	[[ iodine \|Iodine53I126.90]]	[[ xenon \|Xenon54Xe131.29]]
6	[[ caesium \|Caesium55Cs132.91]]	[[ barium \|Barium56Ba137.33]]	[[ lutetium \|Lutetium71Lu174.97]]	[[ hafnium \|Hafnium72Hf178.49]]	[[ tantalum \|Tantalum73Ta180.95]]	[[ tungsten \|Tungsten74W183.84]]	[[ rhenium \|Rhenium75Re186.21]]	[[ osmium \|Osmium76Os190.23]]	[[ iridium \|Iridium77Ir192.22]]	[[ platinum \|Platinum78Pt195.08]]	[[ gold \|Gold79Au196.97]]	[[ Mercury (element)\|Mercury80Hg200.59]]	[[ thallium \|Thallium81Tl204.38]]	[[ lead \|Lead82Pb207.2]]	[[ bismuth \|Bismuth83Bi208.98]]	[[ polonium \|Polonium84Po[209]]]	[[ astatine \|Astatine85At[210]]]	[[ radon \|Radon86Rn[222]]]
7	[[ francium \|Francium87Fr[223]]]	[[ radium \|Radium88Ra[226]]]	[[ lawrencium \|Lawrencium103Lr[266]]]	[[ rutherfordium\|Rutherfordium104Rf[267]]]	[[ dubnium \|Dubnium105Db[268]]]	[[ seaborgium \|Seaborgium106Sg[269]]]	[[ bohrium \|Bohrium107Bh[270]]]	[[ hassium \|Hassium108Hs[269]]]	[[ meitnerium \|Meitnerium109Mt[278]]]	[[ darmstadtium \|Darmstadtium110Ds[281]]]	[[ roentgenium \|Roentgenium111Rg[282]]]	[[ copernicium \|Copernicium112Cn[285]]]	[[ nihonium \|Nihonium113Nh[286]]]	[[ flerovium \|Flerovium114Fl[289]]]	[[ moscovium \|Moscovium115Mc[290]]]	[[ livermorium \|Livermorium116Lv[293]]]	[[ tennessine \|Tennessine117Ts[294]]]	[[ oganesson \|Oganesson118Og[294]]]

			[[ lanthanum \|Lanthanum57La138.91]]	[[ cerium \|Cerium58Ce140.12]]	[[ praseodymium\|Praseodymium59Pr140.91]]	[[ neodymium \|Neodymium60Nd144.24]]	[[ promethium \|Promethium61Pm[145]]]	[[ samarium \|Samarium62Sm150.36]]	[[ europium \|Europium63Eu151.96]]	[[ gadolinium \|Gadolinium64Gd157.25]]	[[ terbium \|Terbium65Tb158.93]]	[[ dysprosium \|Dysprosium66Dy162.50]]	[[ holmium \|Holmium67Ho164.93]]	[[ erbium \|Erbium68Er167.26]]	[[ thulium \|Thulium69Tm168.93]]	[[ ytterbium \|Ytterbium70Yb173.05]]
			[[ actinium \|Actinium89Ac[227]]]	[[ thorium \|Thorium90Th232.04]]	[[ protactinium\|Protactinium91Pa231.04]]	[[ uranium \|Uranium92U238.03]]	[[ neptunium \|Neptunium93Np[237]]]	[[ plutonium \|Plutonium94Pu[244]]]	[[ americium \|Americium95Am[243]]]	[[ curium \|Curium96Cm[247]]]	[[ berkelium \|Berkelium97Bk[247]]]	[[ californium \|Californium98Cf[251]]]	[[ einsteinium \|Einsteinium99Es[252]]]	[[ fermium \|Fermium100Fm[257]]]	[[ mendelevium\|Mendelevium101Md[258]]]	[[ nobelium \|Nobelium102No[259]]]

Primordial From decay Synthetic Border shows natural occurrence of the element

Standard atomic weight A_{r, std}(E)^[1]

Ca: 40.078

— Abridged value (uncertainty omitted here)^[2]

Po: [209] — mass number of the most stable isotope

style="padding:0 1px; background:#ff9999

" | s-block

style="padding:0 1px; background:#9bff99

" | f-block

style="padding:0 1px; background:#99ccff

" | d-block

style="padding:0 1px; background:#fdff8c

" | p-block

↑ Cite error: Invalid <ref> tag; no text was provided for refs named CIAAW2013
↑ Cite error: Invalid <ref> tag; no text was provided for refs named CIAAW2021

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[CIAAW2013-1] Cite error: Invalid <ref> tag; no text was provided for refs named CIAAW2013

[CIAAW2021-2] Cite error: Invalid <ref> tag; no text was provided for refs named CIAAW2021

[1]

[2]

Group	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18
	Hydrogen & alkali metals	Alkaline earth metals											Triels	Tetrels	Pnictogens	Chalcogens	Halogens	Noble gases
Period 1	[[ hydrogen \|Hydrogen1H1.0080]]																	[[ helium \|Helium2He4.0026]]
2	[[ lithium \|Lithium3Li6.94]]	[[ beryllium \|Beryllium4Be9.0122]]											[[ boron \|Boron5B10.81]]	[[ carbon \|Carbon6C12.011]]	[[ nitrogen \|Nitrogen7N14.007]]	[[ oxygen \|Oxygen8O15.999]]	[[ fluorine \|Fluorine9F18.998]]	[[ neon \|Neon10Ne20.180]]
3	[[ sodium \|Sodium11Na22.990]]	[[ magnesium \|Magnesium12Mg24.305]]											[[ aluminium \|Aluminium13Al26.982]]	[[ silicon \|Silicon14Si28.085]]	[[ phosphorus\|Phosphorus15P30.974]]	[[ sulfur \|Sulfur16S32.06]]	[[ chlorine \|Chlorine17Cl35.45]]	[[ argon \|Argon18Ar39.95]]
4	[[ potassium \|Potassium19K39.098]]	[[ calcium \|Calcium20Ca40.078]]	[[ scandium \|Scandium21Sc44.956]]	[[ titanium \|Titanium22Ti47.867]]	[[ vanadium \|Vanadium23V50.942]]	[[ chromium \|Chromium24Cr51.996]]	[[ manganese \|Manganese25Mn54.938]]	[[ iron \|Iron26Fe55.845]]	[[ cobalt \|Cobalt27Co58.933]]	[[ nickel \|Nickel28Ni58.693]]	[[ copper \|Copper29Cu63.546]]	[[ zinc \|Zinc30Zn65.38]]	[[ gallium \|Gallium31Ga69.723]]	[[ germanium \|Germanium32Ge72.630]]	[[ arsenic \|Arsenic33As74.922]]	[[ selenium \|Selenium34Se78.971]]	[[ bromine \|Bromine35Br79.904]]	[[ krypton \|Krypton36Kr83.798]]
5	[[ rubidium \|Rubidium37Rb85.468]]	[[ strontium \|Strontium38Sr87.62]]	[[ yttrium \|Yttrium39Y88.906]]	[[ zirconium \|Zirconium40Zr91.224]]	[[ niobium \|Niobium41Nb92.906]]	[[ molybdenum\|Molybdenum42Mo95.95]]	[[ technetium\|Technetium43Tc[97]]]	[[ ruthenium \|Ruthenium44Ru101.07]]	[[ rhodium \|Rhodium45Rh102.91]]	[[ palladium \|Palladium46Pd106.42]]	[[ silver \|Silver47Ag107.87]]	[[ cadmium \|Cadmium48Cd112.41]]	[[ indium \|Indium49In114.82]]	[[ tin \|Tin50Sn118.71]]	[[ antimony \|Antimony51Sb121.76]]	[[ tellurium \|Tellurium52Te127.60]]	[[ iodine \|Iodine53I126.90]]	[[ xenon \|Xenon54Xe131.29]]
6	[[ caesium \|Caesium55Cs132.91]]	[[ barium \|Barium56Ba137.33]]	[[ lutetium \|Lutetium71Lu174.97]]	[[ hafnium \|Hafnium72Hf178.49]]	[[ tantalum \|Tantalum73Ta180.95]]	[[ tungsten \|Tungsten74W183.84]]	[[ rhenium \|Rhenium75Re186.21]]	[[ osmium \|Osmium76Os190.23]]	[[ iridium \|Iridium77Ir192.22]]	[[ platinum \|Platinum78Pt195.08]]	[[ gold \|Gold79Au196.97]]	[[ Mercury (element)\|Mercury80Hg200.59]]	[[ thallium \|Thallium81Tl204.38]]	[[ lead \|Lead82Pb207.2]]	[[ bismuth \|Bismuth83Bi208.98]]	[[ polonium \|Polonium84Po[209]]]	[[ astatine \|Astatine85At[210]]]	[[ radon \|Radon86Rn[222]]]
7	[[ francium \|Francium87Fr[223]]]	[[ radium \|Radium88Ra[226]]]	[[ lawrencium \|Lawrencium103Lr[266]]]	[[ rutherfordium\|Rutherfordium104Rf[267]]]	[[ dubnium \|Dubnium105Db[268]]]	[[ seaborgium \|Seaborgium106Sg[269]]]	[[ bohrium \|Bohrium107Bh[270]]]	[[ hassium \|Hassium108Hs[269]]]	[[ meitnerium \|Meitnerium109Mt[278]]]	[[ darmstadtium \|Darmstadtium110Ds[281]]]	[[ roentgenium \|Roentgenium111Rg[282]]]	[[ copernicium \|Copernicium112Cn[285]]]	[[ nihonium \|Nihonium113Nh[286]]]	[[ flerovium \|Flerovium114Fl[289]]]	[[ moscovium \|Moscovium115Mc[290]]]	[[ livermorium \|Livermorium116Lv[293]]]	[[ tennessine \|Tennessine117Ts[294]]]	[[ oganesson \|Oganesson118Og[294]]]

			[[ lanthanum \|Lanthanum57La138.91]]	[[ cerium \|Cerium58Ce140.12]]	[[ praseodymium\|Praseodymium59Pr140.91]]	[[ neodymium \|Neodymium60Nd144.24]]	[[ promethium \|Promethium61Pm[145]]]	[[ samarium \|Samarium62Sm150.36]]	[[ europium \|Europium63Eu151.96]]	[[ gadolinium \|Gadolinium64Gd157.25]]	[[ terbium \|Terbium65Tb158.93]]	[[ dysprosium \|Dysprosium66Dy162.50]]	[[ holmium \|Holmium67Ho164.93]]	[[ erbium \|Erbium68Er167.26]]	[[ thulium \|Thulium69Tm168.93]]	[[ ytterbium \|Ytterbium70Yb173.05]]
			[[ actinium \|Actinium89Ac[227]]]	[[ thorium \|Thorium90Th232.04]]	[[ protactinium\|Protactinium91Pa231.04]]	[[ uranium \|Uranium92U238.03]]	[[ neptunium \|Neptunium93Np[237]]]	[[ plutonium \|Plutonium94Pu[244]]]	[[ americium \|Americium95Am[243]]]	[[ curium \|Curium96Cm[247]]]	[[ berkelium \|Berkelium97Bk[247]]]	[[ californium \|Californium98Cf[251]]]	[[ einsteinium \|Einsteinium99Es[252]]]	[[ fermium \|Fermium100Fm[257]]]	[[ mendelevium\|Mendelevium101Md[258]]]	[[ nobelium \|Nobelium102No[259]]]