폴로늄

소개

원자 번호: 84
그룹: 16 or VI A
원자 무게: 209
기간: 6
CAS 번호: 7440-08-6

분류

금속
비금속
금속 비슷한
알칼리 금속
알칼리 토 금속
전이 금속
칼 코겐
할로겐
노블 가스
란타 노이드
악티 노이드
희토류 원소
백금 그룹 금속
초 우라늄
더 안정 동위 원소 없습니다
고체
액체
가스
고체 (예상)

기술 • 용도 / 기능

Polonium was the first element discovered by Mme. Curie in 1898, while seeking the cause of radioactivity of pitchblende from Joachimsthal, Bohemia. The electroscope showed it separating with bismuth. Polonium is also called Radium F. Polonium is a very rare natural element. Uranium ores contain only about 100 mg of the element per ton. Its abundance is only about 0.2% of that of radium. In 1934, it was found that when natural bismuth (bismuth-209) was bombarded by neutrons, bismuth-210, the parent of polonium, was obtained. Milligram amounts of polonium may now be prepared this way, by using the high neutron fluxes of nuclear reactors. Polonium-210 is a low-melting, fairly volatile metal, 50% of which is vaporized in air in 45 hours at 55°C. It is an alpha emitter with a half-life of 138.39 days. A milligram emits as many alpha particles as 5 g of radium. The energy released by its decay is so large (140 W/g) that a capsule containing about half a gram reaches a temperature above 500°C. The capsule also presents a contact gamma-ray dose rate of 0.012 Gy/h. A few curies (1 curie = 3.7 X 10^10 Bq) of polonium exhibit a blue glow, caused by excitation of the surrounding gas. Because almost all alpha radiation is stopped within the solid source and its container, giving up its energy, polonium has attracted attention for uses as a lightweight heat source for thermoelectric power in space satellites. Thirty six isotopes and isomers of polonium are known, with atomic masses ranging from 192 to 218. All are radioactive. Polonium-210 is the most readily available. Isotopes of mass 209 (half-life 102 years) and mass 208 (half-life 2.9 years) can be prepared by alpha, proton, or deuteron bombardment of lead or bismuth in a cyclotron, but these are expensive to produce. Metallic polonium has been prepared from polonium hydroxide and some other polonium compounds in the presence of concentrated aqueous or anhydrous liquid ammonia. Two allotropic modifications are known to exist. Polonium is readily dissolved in dilute acids, but is only slightly soluble in alkalis. Polonium salts of organic acids char rapidly; halide amines are reduced to the metal. Polonium can be mixed or alloyed with beryllium to provide a source of neutrons. It has been used in devices for eliminating static charges in textile mills, etc.; however, beta sources are more commonly used and are less dangerous. It is also used on brushes for removing dust from photographic films. The polonium for these is carefully sealed and controlled, minimizing hazards to the user. Polonium-210 is very dangerous to handle in even milligram or microgram amounts, and special equipment and strict control is necessary. Damage arises from the complete absorption of the energy of the alpha particle into tissue. The maximum permissible body burden for ingested polonium is only 0.03 microcuries, which represents a particle weighing only 6.8 X 10^–12 g. Weight for weight it is about 2.5 X 10^11 times as toxic as hydrocyanic acid. The maximum allowable concentration for soluble polonium compounds in air is about 2 ´ 1011 microcuries/cm^3. Polonium-209 is available commercially on special order from the Oak Ridge National Laboratory at a cost of $3195/microcurie. 1

• "suggested that the isotope 210Po, a natural contaminant of tobacco and an α-particle emitter, might be at least partly responsible fo the incidence of cancer in smokers." 2

물리적 특성

녹는 점:3*  254 °C = 527.15 K = 489.2 °F
비점:3* 962 °C = 1235.15 K = 1763.6 °F
승화 포인트:3 
트리플 포인트:3 
중요 포인트:3 
밀도:4  9.20 g/cm3

* - at 1 atm

전자 구성

전자 구성: [Xe] 6s2 4f14 5d10 6p4
블록: p
최고 점유 에너지 레벨: 6
원자가 전자를: 6

양자 번호:

n = 6
ℓ = 1
m = -1
ms = -½

본딩

전기 음성도 (폴링 규모):5 2.0
Electropositivity (폴링 규모): 2
전자 친화도:6 1.9 eV
산화 미국: +4,2
작업 기능:7 4.6 eV = 7.3692E-19 J

이온화 전위   eV 8  kJ/mol  
이온화 전위   eV 8  kJ/mol  
이온화 전위   eV 8  kJ/mol  
1 8.417    812.1

열화학

비열: 
열 전도성: 20 (W/m)/K, 27°C 9
퓨전의 열: 
기화의 열: 
물질의 상태 형성의 엔탈피 (ΔHf°)10 엔트로피 (S°)10 깁스 자유 에너지 (ΔGf°)10
(kcal/mol) (kJ/mol) (cal/K) (J/K) (kcal/mol) (kJ/mol)
(g) -2.90 -12.1336 53.221 222.676664 -9.84 -41.17056
(s) 0 0 15.0 62.76 0 0
(g) 34.8 145.6032 45.13 188.82392 25.8 107.9472

동위 원소

핵종 질량 11 하프 라이프 11 핵 스핀 11 에너지 바인딩
188Po 187.999422(21) 430(180) μs [0.40(+20-15) ms] 0+ 1,461.00 MeV
189Po 188.998481(24) 5(1) ms 3/2-# 1,469.07 MeV
190Po 189.995101(14) 2.46(5) ms 0+ 1,477.15 MeV
191Po 190.994574(12) 22(1) ms 3/2-# 1,485.22 MeV
192Po 191.991335(13) 32.2(3) ms 0+ 1,493.29 MeV
193Po 192.99103(4) 420(40) ms [370(+46-40) ms] 3/2-# 1,501.36 MeV
194Po 193.988186(13) 0.392(4) s 0+ 1,518.75 MeV
195Po 194.98811(4) 4.64(9) s 3/2-# 1,526.82 MeV
196Po 195.985535(14) 5.56(12) s 0+ 1,534.89 MeV
197Po 196.98566(5) 53.6(10) s (3/2-) 1,542.96 MeV
198Po 197.983389(19) 1.77(3) min 0+ 1,551.03 MeV
199Po 198.983666(25) 5.48(16) min (3/2-) 1,559.10 MeV
200Po 199.981799(15) 11.5(1) min 0+ 1,567.17 MeV
201Po 200.982260(6) 15.3(2) min 3/2- 1,575.25 MeV
202Po 201.980758(16) 44.7(5) min 0+ 1,583.32 MeV
203Po 202.981420(28) 36.7(5) min 5/2- 1,591.39 MeV
204Po 203.980318(12) 3.53(2) h 0+ 1,599.46 MeV
205Po 204.981203(21) 1.66(2) h 5/2- 1,607.53 MeV
206Po 205.980481(9) 8.8(1) d 0+ 1,615.60 MeV
207Po 206.981593(7) 5.80(2) h 5/2- 1,623.67 MeV
208Po 207.9812457(19) 2.898(2) a 0+ 1,631.74 MeV
209Po 208.9824304(20) 102(5) a 1/2- 1,639.82 MeV
210Po 209.9828737(13) 138.376(2) d 0+ 1,647.89 MeV
211Po 210.9866532(14) 0.516(3) s 9/2+ 1,655.96 MeV
212Po 211.9888680(13) 299(2) ns 0+ 1,664.03 MeV
213Po 212.992857(3) 3.65(4) μs 9/2+ 1,662.79 MeV
214Po 213.9952014(16) 164.3(20) μs 0+ 1,670.86 MeV
215Po 214.9994200(27) 1.781(4) ms 9/2+ 1,678.93 MeV
216Po 216.0019150(24) 0.145(2) s 0+ 1,677.68 MeV
217Po 217.006335(7) 1.47(5) s 5/2+# 1,685.76 MeV
218Po 218.0089730(26) 3.10(1) min 0+ 1,693.83 MeV
219Po 219.01374(39)# 2# min [>300 ns] 7/2+# 1,692.58 MeV
220Po 220.01660(39)# 40# s [>300 ns] 0+ 1,700.66 MeV
값은 # 순수 실험 데이터에서 유래하지만, 적어도 부분적으로 체계적인 동향에서되지 않습니다 표시. 약한 할당 인수는 괄호로 묶와 함께 회전합니다. 11

풍부

지구 - 해수: 0.000000000000014 mg/L 12
지구 -  빵 껍질:  0.0000000002 mg/kg = 0.00000000000002% 12

안전 정보


물질 안전 보건 자료 - ACI Alloys, Inc.

자세한 내용은

외부 링크:

저널:
(1) Richard B. Holtzman and Frank H. Ilcewicz, Science 153, 1259-1260 (1966)

소스

(1) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 4:23-4:24.
(2) - Zumdahl, Steven S. Chemistry, 4th ed.: Houghton Mifflin: Boston, 1997; p 916.
(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) - Lide, David R. CRC Handbook of Chemistry and Physics, 84th ed.; CRC Press: Boca Raton, FL, 2002; p 10:147-10:148.
(7) - Speight, James. Lange's Handbook of Chemistry, 16th ed.; McGraw-Hill Professional: Boston, MA, 2004; p 1:132.
(8) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 10:178 - 10:180.
(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) - Lide, David R. CRC Handbook of Chemistry and Physics, 83rd ed.; CRC Press: Boca Raton, FL, 2002; p 14:17.