परिचय
समूह: कोई नहीं
परमाण्विक भार: 140.90765
अवधि: 6
सीएएस संख्या: 7440-10-0
वर्गीकरण
कोई स्थिर आइसोटोप
ठोस
तरल
गैस
ठोस (भविष्यवाणी की)
विवरण • उपयोग करता है / समारोह
In 1841 Mosander extracted the rare earth didymia from lanthana; in 1879, Lecoq de Boisbaudran isolated a new earth, samaria, from didymiaobtained from the mineral samarskite. Six years later, in 1885, von Welsbach separated didymia into two others, praseodymia and neodymia, whichgave salts of different colors. As with other rare earths, compounds of these elements in solution have distinctive sharp spectral absorption bands orlines, some of which are only a few Angstroms wide. The element occurs along with other rare-earth elements in a variety of minerals. Monazite andbastnasite are the two principal commercial sources of the rare-earth metals. Ion-exchange and solvent extraction techniques have led to much easierisolation of the rare earths and the cost has dropped greatly in the past few years. Thirty six isotopes and isomers are now recognized. Praseodymiumcan be prepared by several methods, such as by calcium reduction of the anhydrous chloride of fluoride. Misch metal, used in making cigarette lighters,contains about 5% praseodymium metal. Praseodymium is soft, silvery, malleable, and ductile. It was prepared in relatively pure form in 1931. It issomewhat more resistant to corrosion in air than europium, lanthanum, cerium, or neodymium, but it does develop a green oxide coating that spallsoff when exposed to air. As with other rare-earth metals it should be kept under a light mineral oil or sealed in plastic. The rare-earth oxides, includingPr2O3, are among the most refractory substances known. Along with other rare earths, it is widely used as a core material for carbon arcs used by themotion picture industry for studio lighting and projection. Salts of praseodymium are used to color glasses and enamels; when mixed with certain othermaterials, praseodymium produces an intense and unusually clean yellow color in glass. Didymium glass, of which praseodymium is a component,is a colorant for welder’s goggles. The metal (99.9% pure) is priced at about $2/g. 1
• "tint[s] sunglasses." 2
भौतिक गुण
गलनांक:3* 931 °C = 1204.15 K = 1707.8 °F
ऋणावेशित सूक्ष्म अणु का विन्यास: *[Xe] 6s2 4f3
n = 4
वैद्युतीयऋणात्मकता (पॉलिंग पैमाने):5 1.13
विशिष्ट ताप: 0.193 J/g°C 8 = 27.195 J/mol°C = 0.046 cal/g°C = 6.500 cal/mol°C
पृथ्वी - स्रोत यौगिकों: phosphates 14
बाहरी कड़ियाँ:
पत्रिका:
(1) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 4:24.
क्वथनांक:3* 3520 °C = 3793.15 K = 6368 °F
उच्च बनाने की क्रिया प्वाइंट:3
तीन बिंदु:3
महत्वपूर्ण बिंदु:3
घनत्व:4 6.77 g/cm3
* - at 1 atm
ऋणावेशित सूक्ष्म अणु का विन्यास
खंड: f
उच्चतम अधिकृत एनर्जी लेवल: 6
अणु की संयोजन क्षमता: 2
क्वांटम संख्याएं:
ℓ = 3
mℓ = -1
ms = +½
संबंध
Electropositivity (पॉलिंग पैमाने): 2.87
समारोह का कार्य:6 2.7 eV = 4.3254E-19 J
आयनीकरण क्षमता
eV 7
kJ/mol
1
5.473
528.1
आयनीकरण क्षमता
eV 7
kJ/mol
2
10.55
1017.9
3
21.624
2086.4
आयनीकरण क्षमता
eV 7
kJ/mol
4
38.98
3761.0
5
57.53
5550.8
ऊष्मारसायन
ऊष्मीय चालकता: 12.5 (W/m)/K, 27°C 9
फ्यूजन की गर्मी: 6.89 kJ/mol 10 = 48.9 J/g
वाष्पीकरण की ऊष्मा: 296.8 kJ/mol 11 = 2106.3 J/g
पदार्थ की अवस्था
गठन की तापीय धारिता (ΔHf°)12
entropy (S°)12
गिब्स नि: शुल्क ऊर्जा (ΔGf°)12
(kcal/mol)
(kJ/mol)
(cal/K)
(J/K)
(kcal/mol)
(kJ/mol)
(s)
0
0
17.5
73.22
0
0
(g)
85.0
355.64
45.34
189.70256
76.7
320.9128
आइसोटोप
nuclide
सामूहिक 13
हाफ लाइफ 13
परमाणु स्पिन 13
बंधन ऊर्जा
121Pr
120.95536(75)#
600(300) ms
(3/2-)
977.04 MeV
122Pr
121.95181(54)#
500# ms
985.12 MeV
123Pr
122.94596(64)#
800# ms
3/2+#
1,002.50 MeV
124Pr
123.94296(64)#
1.2(2) s
1,010.57 MeV
125Pr
124.93783(43)#
3.3(7) s
3/2+#
1,027.96 MeV
126Pr
125.93531(21)#
3.12(18) s
(4,5,6)
1,036.03 MeV
127Pr
126.93083(21)#
4.2(3) s
3/2+#
1,044.10 MeV
128Pr
127.92879(3)
2.84(9) s
(3+)
1,061.49 MeV
129Pr
128.92510(3)
32(3) s
(11/2-)
1,069.56 MeV
130Pr
129.92359(7)
40.0(4) s
(6,7)(+#)
1,077.63 MeV
131Pr
130.92026(6)
1.50(3) min
(3/2+)
1,085.70 MeV
132Pr
131.91926(6)
1.49(11) min
(2+)
1,103.09 MeV
133Pr
132.916331(13)
6.5(3) min
(3/2+)
1,111.16 MeV
134Pr
133.91571(4)
~11 min
(5-)
1,119.23 MeV
135Pr
134.913112(13)
24(2) min
3/2(+)
1,127.30 MeV
136Pr
135.912692(13)
13.1(1) min
2+
1,135.37 MeV
137Pr
136.910705(13)
1.28(3) h
5/2+
1,143.44 MeV
138Pr
137.910755(15)
1.45(5) min
1+
1,151.52 MeV
139Pr
138.908938(8)
4.41(4) h
5/2+
1,168.90 MeV
140Pr
139.909076(7)
3.39(1) min
1+
1,176.97 MeV
141Pr
140.9076528(26)
स्थिर
5/2+
1,185.04 MeV
142Pr
141.9100448(26)
19.12(4) h
2-
1,183.80 MeV
143Pr
142.9108169(28)
13.57(2) d
7/2+
1,191.87 MeV
144Pr
143.913305(4)
17.28(5) min
0-
1,199.94 MeV
145Pr
144.914512(8)
5.984(10) h
7/2+
1,208.02 MeV
146Pr
145.91764(7)
24.15(18) min
(2)-
1,216.09 MeV
147Pr
146.918996(25)
13.4(4) min
(3/2+)
1,224.16 MeV
148Pr
147.922135(28)
2.29(2) min
1-
1,222.91 MeV
149Pr
148.92372(9)
2.26(7) min
(5/2+)
1,230.99 MeV
150Pr
149.926673(28)
6.19(16) s
(1)-
1,239.06 MeV
151Pr
150.928319(25)
18.90(7) s
(3/2)(-#)
1,247.13 MeV
152Pr
151.93150(13)
3.63(12) s
4+
1,245.88 MeV
153Pr
152.93384(11)
4.28(11) s
5/2-#
1,253.96 MeV
154Pr
153.93752(16)
2.3(1) s
(3+,2+)
1,262.03 MeV
155Pr
154.94012(32)#
1# s [>300 ns]
5/2-#
1,260.78 MeV
156Pr
155.94427(43)#
500# ms [>300 ns]
1,268.85 MeV
157Pr
156.94743(43)#
300# ms
5/2-#
1,276.93 MeV
158Pr
157.95198(64)#
200# ms
1,275.68 MeV
159Pr
158.95550(75)#
100# ms
5/2-#
1,283.75 MeV
मान चिह्नित # विशुद्ध रूप से प्रयोगात्मक डेटा से प्राप्त नहीं कर रहे हैं, लेकिन कम से कम आंशिक रूप से व्यवस्थित प्रवृत्तियों से। Spins कमजोर तर्क के साथ काम कोष्ठकों में संलग्न हैं। 13
प्रचुरता
पृथ्वी - समुद्र के पानी: 0.00000064 mg/L 15
पृथ्वी -
भूपटल:
9.2 mg/kg = 0.00092% 15
पृथ्वी -
कुल:
129 ppb 16
पारा ग्रह) -
कुल:
99 ppb 16
शुक्र -
कुल:
135 ppb 16
Chondrites - कुल: 0.14 (relative to 106 atoms of Si) 17
यौगिकों
praseodymium(II) iodide
praseodymium(II) selenide
praseodymium(II) sulfide
praseodymium(II) telluride
praseodymium(III) bromide
सुरक्षा जानकारी
सामग्री सुरक्षा डाटा शीट - ACI Alloys, Inc.
अधिक जानकारी के लिए
American Elements
Chemical & Engineering News
Chemical Elements
ChemGlobe
Chemicool
Environmental Chemistry
(1) Folger, Tim. The Secret Ingredients of Everything. National Geographic, June 2011, pp 136-145.
सूत्रों का कहना है
(2) - Folger, Tim. The Secret Ingredients of Everything. National Geographic, June 2011, p 140.
(3) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 4:132.
(4) - Lide, David R. CRC Handbook of Chemistry and Physics, 84th ed.; CRC Press: Boca Raton, FL, 2002; p 4:39-4:96.
(5) - Dean, John A. Lange's Handbook of Chemistry, 11th ed.; McGraw-Hill Book Company: New York, NY, 1973; p 4:8-4:149.
(6) - Speight, James. Lange's Handbook of Chemistry, 16th ed.; McGraw-Hill Professional: Boston, MA, 2004; p 1:132.
(7) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 10:178 - 10:180.
(8) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 4:133.
(9) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; pp 6:193, 12:219-220.
(10) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; pp 6:123-6:137.
(11) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; pp 6:107-6:122.
(12) - Dean, John A. Lange's Handbook of Chemistry, 12th ed.; McGraw-Hill Book Company: New York, NY, 1979; p 9:4-9:94.
(13) - Atomic Mass Data Center. http://amdc.in2p3.fr/web/nubase_en.html (accessed July 14, 2009).
(14) - Silberberg, Martin S. Chemistry: The Molecular Nature of Matter and Change, 4th ed.; McGraw-Hill Higher Education: Boston, MA, 2006, p 965.
(15) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 14:17.
(16) - Morgan, John W. and Anders, Edward, Proc. Natl. Acad. Sci. USA 77, 6973-6977 (1980)
(17) - Brownlow, Arthur. Geochemistry; Prentice-Hall, Inc.: Englewood Cliffs, NJ, 1979, pp 15-16.