Presidimyo

Ang Praseodimyo o Praseodymium ay isang elementong kimikal na may simbolong Pr at bilang atomikong 59. Ang Praseodimyo ay isang malambot, mapilak, maleable at duktilong metal sa pangkat lantanido. Ito ay labis na reaktibo na matatagpuan sa likas na anyo at kapag inihandang artipisyal ay mabagal na bumubuo ng isang luntiang oksidong pagpapahid. Ang elementong ito ay ipinangalan para sa kulay ng pangunahing oksido nito. Noong 1841, kinuha ng kimikong Swedish si Carl Gustav Mosander ang isang bihirang mundong oksidong labi na kanyang tinawag na "didymium" mula sa isang labi kanyang "lantana" na hinawalay naman mula sa asing seryo. Noong 1885, hiniawalay ng kimikong Austriyano na si Baron Carl Auer von Welsbach ang didymium sa dalawang mga asin ng magkakaibang mga kulay na kanyang tinawag na praseodymium at neodymium. Ang pangalang praseodymium ay nagmula sa salitang Griyegong prasios (πράσιος) na nangangahulugang luntian at didymos (δίδυμος) na nangangahulugang kambal. Tulad ng karamihang mga elementong bihirang mundo, ang praseodymium ay pinakahandang bumubuo ng tribalenteng Pr(III) mga ion. Ang mga ito ay dilaw-luntian sa solusyong tubig at iba't ibang mga lilim ng dilaw-bered kapag isinama sa mga salamin. Marami sa mga gamit industriyal ng praseodimyo ay kinasasangkutan ng panalang liwanag na dilay mula sa mga pinagmulang liwanag.

Praseodymium, ₅₉Pr

Praseodymium
Bigkas	/ˌpreɪziːəˈdɪmiəm/[1] ​(PRAY-zee-ə-DIM-ee)
Appearance	grayish white
Standard atomic weight Ar°(Pr)
	140.90766±0.00001 140.91±0.01 (pinaikli)[2][3]
Praseodymium sa talahanayang peryodiko
Hydrogen Helium Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson – ↑ Pr ↓ Pa cerium ← praseodymium → neodymium
Atomikong bilang (Z)	59
Group	n/a
Period	6
Block	f-block
Electron configuration	[Xe] 4f3 6s2
Electrons per shell	2, 8, 18, 21, 8, 2
Physical properties
Phase at STP	solido
Melting point	1204 K ​(931 °C, ​1708 °F)[4]
Boiling point	3403 K ​(3130 °C, ​5666 °F)
Density (at 20° C)	6.773 g/cm3 [4]
when liquid (at m.p.)	6.50 g/cm3
Heat of fusion	6.89 kJ/mol
Heat of vaporization	331 kJ/mol
Molar heat capacity	27.20 J/(mol·K)
Vapor pressure P (Pa) 1 10 100 1 k 10 k 100 k at T (K) 1771 1973 (2227) (2571) (3054) (3779)
Atomic properties
Oxidation states	0,[5] +1,[6] +2, +3, +4, +5 (isang katamtamang panimulang oksido)
Electronegativity	Pauling scale: 1.13
Ionization energies	1st: 527 kJ/mol 2nd: 1020 kJ/mol 3rd: 2086 kJ/mol
Atomic radius	empirical: 182 pm
Covalent radius	203±7 pm
Mga linyang espektral ng praseodymium
Other properties
Crystal structure	​double hexagonal close-packed (dhcp) (hP4)
Lattice constants	a = 0.36723 nm c = 1.18328 nm (at 20 °C)[4]
Thermal expansion	4.5×10−6/K (at 20 °C)[4][a]
Thermal conductivity	12.5 W/(m⋅K)
Electrical resistivity	poly: 0.700 µΩ⋅m (at r.t.)
Magnetic ordering	paramagnetic[7]
Molar magnetic susceptibility	+5010.0×10−6 cm3/mol (293 K)[8]
Young's modulus	37.3 GPa
Shear modulus	14.8 GPa
Bulk modulus	28.8 GPa
Speed of sound thin rod	2280 m/s (at 20 °C)
Poisson ratio	0.281
Vickers hardness	250–745 MPa
Brinell hardness	250–640 MPa
CAS Number	7440-10-0
History
Discovery	Carl Auer von Welsbach (1885)
Isotopes of praseodymium t b
Main isotopes[9] Decay abun­dance half-life (t1/2) mode pro­duct 141Pr 100% stable 142Pr synth 19.12 h β− 142Nd ε 142Ce 143Pr synth 13.57 d β− 143Nd
Kategorya: Praseodymium tingnan usapan baguhin | references

Mga sanggunian

1. "praseodymium". Oxford English Dictionary (sa wikang Ingles) (ika-3 (na) edisyon). Oxford University Press. Setyembre 2005.{{cite book}}: CS1 maint: date auto-translated (link)
2. "Standard Atomic Weights: Praseodymium" (sa wikang Ingles). CIAAW. 2017.{{cite web}}: CS1 maint: date auto-translated (link)
3. Prohaska, Thomas; Irrgeher, Johanna; Benefield, Jacqueline; Böhlke, John K.; Chesson, Lesley A.; Coplen, Tyler B.; Ding, Tiping; Dunn, Philip J. H.; Gröning, Manfred; Holden, Norman E.; Meijer, Harro A. J. (2022-05-04). "Standard atomic weights of the elements 2021 (IUPAC Technical Report)". Pure and Applied Chemistry (sa wikang Ingles). doi:10.1515/pac-2019-0603. ISSN 1365-3075.{{cite journal}}: CS1 maint: date auto-translated (link)
4. Arblaster, John W. (2018). Selected Values of the Crystallographic Properties of Elements. Materials Park, Ohio: ASM International. ISBN 978-1-62708-155-9.{{cite book}}: CS1 maint: date auto-translated (link)
5. Yttrium and all lanthanides except Ce and Pm have been observed in the oxidation state 0 in bis(1,3,5-tri-t-butylbenzene) complexes, see Cloke, F. Geoffrey N. (1993). "Zero Oxidation State Compounds of Scandium, Yttrium, and the Lanthanides". Chem. Soc. Rev. 22: 17–24. doi:10.1039/CS9932200017.{{cite journal}}: CS1 maint: date auto-translated (link) and Arnold, Polly L.; Petrukhina, Marina A.; Bochenkov, Vladimir E.; Shabatina, Tatyana I.; Zagorskii, Vyacheslav V.; Cloke (2003-12-15). "Arene complexation of Sm, Eu, Tm and Yb atoms: a variable temperature spectroscopic investigation". Journal of Organometallic Chemistry (sa wikang Ingles). 688 (1–2): 49–55. doi:10.1016/j.jorganchem.2003.08.028.{{cite journal}}: CS1 maint: date auto-translated (link)
6. Chen, Xin; atbp. (2019-12-13). "Lanthanides with Unusually Low Oxidation States in the PrB^3– and PrB^4– Boride Clusters". Inorganic Chemistry (sa wikang Ingles). 58 (1): 411–418. doi:10.1021/acs.inorgchem.8b02572. PMID 30543295.{{cite journal}}: CS1 maint: date auto-translated (link)
7. Jackson, M. (2000). "Magnetism of Rare Earth" (PDF). The IRM quarterly. 10 (3): 1.{{cite journal}}: CS1 maint: date auto-translated (link)
8. Weast, Robert (1984). CRC, Handbook of Chemistry and Physics. Boca Raton, Florida: Chemical Rubber Company Publishing. pp. E110. ISBN 0-8493-0464-4.{{cite book}}: CS1 maint: date auto-translated (link)
9. Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3): 030001. doi:10.1088/1674-1137/abddae.{{cite journal}}: CS1 maint: date auto-translated (link)

1. The thermal expansion is highly anisotropic: the parameters (at 20 °C) for each crystal axis are α_a = 1.4×10⁻⁶/K, α_c = 10.8×10⁻⁶/K, and α_average = α_V/3 = 4.5×10⁻⁶/K.