Gold (Au)
transition-metalSolid
표준 원자량
196.966569 u전자 배치
[Xe] 6s1 4f14 5d10녹는점
1064.18 °C끓는점
2855.85 °C밀도
1.9282e+4 kg/m³산화 상태
−3, −2, −1, 0, +1, +2, +3, +5전기 음성도(Pauling)
2.54제1 이온화 에너지
9.225554 eV발견 연도
해당 없음원자 반지름
135 pm상세 정보
Gold is a dense, soft transition metal with exceptional resistance to oxidation and corrosion. It is usually found native or alloyed with silver and other precious metals, rather than as common simple ores. Its chemistry is dominated by relativistic effects, which help give the metal its yellow color and influence stable oxidation states. Gold combines high electrical conductivity, malleability, chemical nobility, and cultural value in a way unmatched by most elements.
It is estimated that all the gold in the world, so far refined, could be placed in a single cube 60 ft. on a side. Of all the elements, gold in its pure state is undoubtedly the most beautiful. It is metallic, having a yellow color when in a mass, but when finely divided it may be black, ruby, or purple. The Purple of Cassius is a delicate test for auric gold. It is the most malleable and ductile metal; 1 oz. of gold can be beaten out to 300 ft2. It is a soft metal and is usually alloyed to give it more strength. It is a good conductor of heat and electricity, and is unaffected by air and most reagents.
The name derives from the Sanskrit jval for "shine", the Teutonic word gulth for "shining metal", and the Anglo-Saxon gold of unknown origin. The symbol Au derives from the Latin aurum, for Aurora, the goddess of dawn. Gold was known and highly valued in prehistoric times.
An attractive and highly valued metal, gold has been known for at least 5500 years. Gold is sometimes found free in nature but it is usually found in conjunction with silver, quartz (SiO2), calcite (CaCO3), lead, tellurium, zinc or copper. There is roughly 1 milligram of gold dissolved in every ton of seawater, although extracting it currently costs more than the gold is worth. It has been estimated that all of the gold that has currently been refined could be placed in a cube measuring 20 meters on a side.
Known and highly valued from earliest times, gold is found in nature as the free metal and in tellurides; it is very widely distributed and is almost always associated with quartz or pyrite.
Pure gold is a bright metallic yellow solid at ordinary conditions. It is very malleable and ductile, and freshly exposed surfaces keep their luster in air. Finely divided gold can appear red, purple, or blue because small particles interact with light differently from bulk metal.
Gold is used in jewelry, coinage, bullion, and decorative gilding, often alloyed to improve hardness. In electronics it is valued for corrosion-resistant contacts, bond wires, connectors, and thin coatings. Dentistry has used gold alloys where durability and biocompatibility are important, though use has declined in some settings. Gold nanoparticles are used in diagnostic tests, research reagents, and specialized optical materials. Radioactive ¹⁹⁸Au has had limited medical and tracer applications.
Gold is the most malleable and ductile of all known metals. A single ounce of gold can be beaten into a sheet measuring roughly 5 meters on a side. Thin sheets of gold, known as gold leaf, are primarily used in arts and crafts for gilding. One sheet of gold leaf can be as thin as 0.000127 millimeters, or about 400 times thinner than a human hair.
Pure gold is soft and is usually alloyed with other metals, such as silver, copper, platinum or palladium, to increase its strength. Gold alloys are used to make jewelry, decorative items, dental fillings and coins. The amount of gold in an alloy is measured with a unit called a karat. One karat is equal to one part in twenty-four, so an 18 karat gold ring contains 18 parts pure gold and 6 parts alloy material.
Gold is a good conductor of heat and electricity and does not tarnish when it is exposed to the air, so it can be used to make electrical connectors and printed circuit boards. Gold is also a good reflector of infrared radiation and can be used to help shield spacecraft and skyscrapers from the sun's heat. Gold coated mirrors can be used to make telescopes that are sensitive to infrared light.
A radioactive isotope of gold, gold-198, is used for treating cancer. Gold sodium thiosulfate (AuNa3O6S4) is used as a treatment for arthritis. Chlorauric acid (HAuCl4) is used to preserve photographs by replacing the silver atoms present in an image.
It is used in coinage and is a standard for monetary systems in many countries. It is also extensively used for jewelry, decoration, dental work, and for plating. It is used for coating certain space satellites, as it is a good reflector of infrared and is inert.
Isotopes in Biology
195Au (with a half-life of about 0.51 year) has been used to study particle movement within the lungs of rats [528] G. Patrick, C. Stirling. Environ. Health Perspect.97, 47 (1992).. 198Au (with a half-life of 2.7 days) was used in a study to model gold cycling in plants. This study demonstrated that gold particles are retained by humates (organic constituents of soil), which contain fulvic acid, humic acid, ulmic acid, and lignin and would therefore be likely to accumulate in mull humus or forest litter [529] K. C. Jones, P. J. Peterson. Biogeochemistry7, 3 (1989)..
Isotopes in Medicine
198Au has several medical uses. It has been used as both a diagnostic tool and a treatment option for cancer [530] N. Chanda, P. Kan, L. D. Watkinson, R. Shukla, A. Zambre, T. L. Carmack, H. Engelbrecht, J. R. Lever, K. Katti, G. M. Fent, S. W. Casteel, C. J. Smith, W. H. Miller, S. Jurisson, E. Boote, J. D. Robertson, C. Cutler, M. Dobrovolskaia, R. Kannan, K. V. Katti. Nanomed-Nanotechnol.6, 201 (2010)., [531] C. W. H. Havard, J. McAlister. Br. Med. J.2, 555 (1967)..
–As a diagnostic tool, colloidal 198Au is injected into the affected organ. Normal cells will take up the gold colloid, but tumor cells will not. Therefore, an abscess will show up as a “cold area” on a scan [531] C. W. H. Havard, J. McAlister. Br. Med. J.2, 555 (1967)..
–As a treatment option, gold is intended to provide localized irradiation and can be implanted or injected into the affected area. When implanted, the gold “seed” offers an advantage over other materials in that it can be left in place due to its short half-life (2.7 days). As a colloidal injection, 198Au has been found to produce improvement from a wide variety of cancers [530] N. Chanda, P. Kan, L. D. Watkinson, R. Shukla, A. Zambre, T. L. Carmack, H. Engelbrecht, J. R. Lever, K. Katti, G. M. Fent, S. W. Casteel, C. J. Smith, W. H. Miller, S. Jurisson, E. Boote, J. D. Robertson, C. Cutler, M. Dobrovolskaia, R. Kannan, K. V. Katti. Nanomed-Nanotechnol.6, 201 (2010).. Figure 4.79.1a and 4.79.1b, respectively, show squamous cell carcinoma (cancer) on the lower left eyelid of a cat and the eyelid 6 weeks after implantation of 198Au seeds [532] C. Hardman, R. Stanley. Aust. Vet. J.79, 604 (2001)..
Recent studies have shown the effectiveness of 198Au nanoparticles and nanodevices in reducing tumor size in mice while minimizing radiation spread to other areas [530] N. Chanda, P. Kan, L. D. Watkinson, R. Shukla, A. Zambre, T. L. Carmack, H. Engelbrecht, J. R. Lever, K. Katti, G. M. Fent, S. W. Casteel, C. J. Smith, W. H. Miller, S. Jurisson, E. Boote, J. D. Robertson, C. Cutler, M. Dobrovolskaia, R. Kannan, K. V. Katti. Nanomed-Nanotechnol.6, 201 (2010)., [533] M. K. Khan, L. D. Minc, S. S. Nigavekar, M. S. T. Kariapper, B. M. Nair, M. Schipper, A. C. Cook, W. G. Lesniak, L. P. Balogh. Nanomedicine4, 57 (2008)., [534] H. B. Wheeler, W. E. Jaques, T. W. Botsford. Ann. Surg.141, 208 (1955).. 198Au has been studied and successfully used as an anti-inflammatory (a substance or treatment that reduces the body tissues response to harmful stimuli, such as swelling) for improving arthritic conditions [535] A. M. Spencer, M. P. Patel, B. J. Smits, J. D. F. Williams. Br. Med. J.4 (5937), 153 (1974)., [536] J. R. Topp, E. G. Cross, A. G. Fam. Can. Med. Assoc. J.112, 1085 (1975)..
Gold commonly forms compounds in the +1 and +3 oxidation states, while metallic gold is unusually noble. Chloroauric acid, HAuCl₄, is an important laboratory and refining intermediate, and tetrachloroaurate(III), [AuCl₄]⁻, is a common soluble gold complex. Gold(I) cyanide, AuCN, and dicyanoaurate(I), [Au(CN)₂]⁻, are central to cyanide leaching. Gold forms stable complexes with soft donor ligands such as phosphines, sulfides, and thiolates. Simple gold oxides are relatively unstable compared with those of many transition metals.
See more information at the Gold compound page.
Bulk metallic gold is chemically inert and is generally not a major toxicity hazard, but powders and fumes can present exposure risks in industrial work. Soluble gold salts may be irritants, sensitizers, or systemically toxic, depending on the compound. Cyanide-based gold processing involves hazards from cyanide salts and hydrogen cyanide, HCN, rather than from gold itself. Radioactive gold isotopes require isotope-specific radiation controls.
Gold occurs naturally at very low concentrations in rocks, sediments, seawater, and hydrothermal deposits. Weathering can release native particles that accumulate in placer deposits because of gold's high density and chemical persistence. In soils and waters, gold is usually immobile, but complexation by chloride, cyanide, thiosulfate, or organic sulfur compounds can increase transport. Mining and processing can disturb large volumes of material and may release associated elements such as arsenic or mercury where they are present.
Gold is mined from hard-rock deposits and placers, and is also recovered as a by-product from some copper, nickel, and polymetallic ores. Extraction commonly uses gravity concentration, flotation, smelting, and cyanide leaching, depending on ore type. Supply is supplemented by extensive recycling from jewelry, electronics, and industrial scrap. Demand is split among jewelry, investment, central-bank reserves, and technology. Because gold is highly valued and chemically durable, much of the metal ever refined remains recoverable, although dispersed uses in electronics can be difficult to reclaim economically.
It occurs in veins and alluvial deposits, and is often separated from rocks and other minerals by mining and panning operations. About two thirds of the world's gold output comes from South Africa, and about two thirds of the total U.S. production comes from South Dakota and Nevada. The metal is recovered from its ores by cyaniding, amalgamating, and smelting processes. Refining is also frequently done by electrolysis. Gold occurs in sea water to the extent of 0.1 to 2 mg/ton, depending on the location where the sample is taken. As yet, no method has been found for recovering gold from sea water profitably.
Gold is a rare heavy element in the cosmos. It is produced mainly by rapid neutron-capture nucleosynthesis, with neutron-star mergers strongly implicated and some contribution from rare supernova environments possible. In the early Solar System, gold partitioned strongly into metallic phases, so much of Earth's original inventory is thought to reside in the core. Crustal gold is concentrated by later geological processes.
- Gold can be beaten into leaf thin enough to transmit greenish light.
- The symbol Au comes from the Latin name aurum.
- Gold is one of the few metals that is strongly yellow in bulk form.
- Native gold commonly contains silver; electrum is a natural gold-silver alloy.
- Gold's resistance to tarnish makes it useful for low-current electrical contacts.
- Aqua regia dissolves gold by combining oxidation with chloride complex formation.
이미지
특성
물리적 특성
- 원자 반지름(경험값)
- 135 pm 모든 원소의 원자 반지름(경험값) 비교 →
- 공유 결합 반지름
- 136 pm 모든 원소의 공유 결합 반지름 비교 →
- 반데르발스 반지름
- 166 pm 모든 원소의 반데르발스 반지름 비교 →
- 금속 반지름
- 134 pm 모든 원소의 금속 반지름 비교 →
- 밀도
- 1.9282 × 104 kg/m³ 모든 원소의 밀도 비교 →
- 몰 부피
- 0.0102 L/mol
- STP에서의 상
- 고체 모든 원소의 STP에서의 상 비교 →
- 녹는점
- 1064.18 °C 모든 원소의 녹는점 비교 →
- 끓는점
- 2855.85 °C 모든 원소의 끓는점 비교 →
- 열전도율
- 318 W/(m·K) 모든 원소의 열전도율 비교 →
- 비열
- 0.129 J/(g·K) 모든 원소의 비열 비교 →
- 몰 열용량
- 25.418 J/(mol·K) 모든 원소의 몰 열용량 비교 →
- 결정 구조
- 면심 입방 모든 원소의 결정 구조 비교 →
화학적 특성
- 전기 음성도(Pauling)
- 2.54 모든 원소의 전기 음성도(Pauling) 비교 →
- 전기 음성도(Allen)
- 1.92
- 전자 친화도
- 2.3086 eV
- 제1 이온화 에너지
- 9.225554 eV 모든 원소의 제1 이온화 에너지 비교 →
- 제2 이온화 에너지
- 20.20307 eV 모든 원소의 제2 이온화 에너지 비교 →
- 제3 이온화 에너지
- 30.000103 eV 모든 원소의 제3 이온화 에너지 비교 →
- 제4 이온화 에너지
- 45.000155 eV 모든 원소의 제4 이온화 에너지 비교 →
- 제5 이온화 에너지
- 60.000207 eV 모든 원소의 제5 이온화 에너지 비교 →
- 산화 상태
- −3, −2, −1, 0, +1, +2, +3, +5 모든 원소의 산화 상태 비교 →
- 원자가 전자
- 11 모든 원소의 원자가 전자 비교 →
- 전자 배치
- [Xe] 6s1 4f14 5d10
열역학적 특성
- 융해열
- 0.13007203 eV 모든 원소의 융해열 비교 →
- 기화열
- 3.358035 eV 모든 원소의 기화열 비교 →
- 승화열
- 3.814064 eV
- 원자화열
- 3.814064 eV
- 원자화 엔탈피
- 3.816137 eV
핵 특성
- 양성자 수
- 79 모든 원소의 양성자 수 비교 →
- 중성자 수
- 118 모든 원소의 중성자 수 비교 →
- 알려진 동위원소 수
- 43 모든 원소의 알려진 동위원소 수 비교 →
- 안정 동위원소 수
- 1 모든 원소의 안정 동위원소 수 비교 →
- 가장 안정한 동위원소
- Au-197
존재비
- 존재비(지각)
- 0.004 mg/kg 모든 원소의 존재비(지각) 비교 →
- 존재비(해양)
- 4 × 10−6 mg/L 모든 원소의 존재비(해양) 비교 →
결정 구조
- 격자 상수 a
- 408 pm
전자 구조
- 전자껍질별 전자 수
- 2, 8, 18, 32, 18, 1 모든 원소의 전자껍질별 전자 수 비교 →
식별자
- CAS 등록 번호
- 7440-57-5 모든 원소의 CAS 등록 번호 비교 →
- 항 기호
- 2S1/2
- InChI
- InChI=1S/Au
- InChI 키
- PCHJSUWPFVWCPO-UHFFFAOYSA-N
전자 배치 측정값
Au: 4f¹⁴ 5d¹⁰ 6s¹[Xe] 4f¹⁴ 5d¹⁰ 6s¹1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ 4f¹⁴ 5d¹⁰ 6s¹원자 모형
동위원소에 따라 중성자 수, 질량, 안정성은 달라지지만, 중성 원자의 전자 배치는 달라지지 않습니다.
개략적인 원자 모형이며 실제 비율과 다릅니다.
원자 지문
방출 / 흡수 스펙트럼
동위원소 분포
| 질량수 | 원자 질량(u) | 천연 존재비 | 반감기 |
|---|---|---|---|
| 197 안정 | 196.96656879 ± 0.00000071 | 100.0000% | 안정 |
상 / 상태
이유: 녹는점(1064.18 °C)보다 1039.2 °C 낮음
개략도이며 실제 비율과 다름
상전이점
전이 에너지
녹는점에서 1 mol을 녹이는 데 필요한 에너지
끓는점에서 1 mol을 기화시키는 데 필요한 에너지
승화점에서 1 mol을 승화시키는 데 필요한 에너지
밀도
표준 조건에서
표준 조건에서
원자 스펙트럼
전체 79개 중 10개를 표시합니다. 이온 전하순으로 정렬되었습니다(오름차순).
보유 에너지 준위 데이터 ?
| 이온 | 전하 | 준위 |
|---|---|---|
| Au I | 0 | 75 |
| Au II | +1 | 48 |
| Au III | +2 | 2 |
| Au IV | +3 | 2 |
| Au V | +4 | 2 |
| Au VI | +5 | 2 |
| Au VII | +6 | 2 |
| Au VIII | +7 | 2 |
| Au IX | +8 | 2 |
| Au X | +9 | 2 |
이온 반지름
| 전하 | 배위 | 스핀 | 반지름 |
|---|---|---|---|
| +1 | 6 | 해당 없음 | 137 pm |
| +3 | 4 | 해당 없음 | 68 pm |
| +3 | 6 | 해당 없음 | 85 pm |
| +5 | 6 | 해당 없음 | 56.99999999999999 pm |
화합물
동위원소 (1)
The most common gold compounds are auric chloride and chlorauric acid, the latter being used in photography for toning the silver image. Gold has 18 isotopes; 198Au, with a half-life of 2.7 days, is used for treating cancer and other diseases. Disodium aurothiomalate is administered intramuscularly as a treatment for arthritis. A mixture of one part nitric acid with three of hydrochloric acid is called aqua regia (because it dissolved gold, the King of Metals). Gold is available commercially with a purity of 99.999+%. For many years the temperature assigned to the freezing point of gold has been 1063.0C; this has served as a calibration point for the International Temperature Scales (ITS-27 and ITS-48) and the International Practical Temperature Scale (IPTS-48). In 1968, a new International Practical Temperature Scale (IPTS-68) was adopted, which demands that the freezing point of gold be changed to 1064.43C. The specific gravity of gold has been found to vary considerably depending on temperature, how the metal is precipitated, and cold-worked.
| 질량수 | 원자 질량(u) | 천연 존재비 | 반감기 | 붕괴 방식 | |
|---|---|---|---|---|---|
| 197 안정 | 196.96656879 ± 0.00000071 | 100.0000% | 안정 | stable |
확장 특성
공유 결합 반지름(확장)
- 공유 결합 반지름(Pyykkö)
- 124 pm
- 공유 결합 반지름(Pyykkö, 이중 결합)
- 121 pm
- 공유 결합 반지름(Pyykkö, 삼중 결합)
- 123 pm
반데르발스 반지름
- Batsanov
- 210 pm
- Alvarez
- 232 pm
- UFF
- 329.3 pm
- MM3
- 243 pm
원자 및 금속 반지름
- 원자 반지름(Rahm)
- 226 pm
- 금속 반지름(C12)
- 144 pm
번호 척도
- Mendeleev
- 73
- Pettifor
- 70
- Glawe
- 66
전기 음성도 척도
- Ghosh
- 0
- Miedema
- 5
- Gunnarsson–Lundqvist
- 5
- Robles–Bartolotti
- 4
분극률 및 분산
- 쌍극자 분극률
- 36 a.u.
- 쌍극자 분극률(불확도)
- 3 a.u.
- C₆ (Gould–Bučko)
- 427 Ha·Bohr6
미데마 매개변수
- 미데마 몰 부피
- 10.2 cm3/mol
- 미데마 전자 밀도
- 4
공급 위험 및 경제성
- 생산 집중도
- 13
- 상대적 공급 위험
- 6
- 매장량 분포
- 15
- 정치적 안정성(최대 생산국)
- 24
- 정치적 안정성(최대 매장국)
- 75
상전이 및 동소체
| 녹는점 | 1337.33 K |
| 끓는점 | 3109.15 K |
산화 상태 분류
심화 참고 데이터
차폐 상수 (14)
| n | 오비탈 | σ |
|---|---|---|
| 1 | s | 1.5239 |
| 2 | p | 4.4868 |
| 2 | s | 20.6302 |
| 3 | d | 13.4917 |
| 3 | p | 22.297 |
| 3 | s | 23.2372 |
| 4 | d | 37.472 |
| 4 | f | 38.3504 |
| 4 | p | 35.4532 |
| 4 | s | 34.5868 |
결정 반지름 상세 정보 (4)
| 전하 | CN | 스핀 | rcrystal (pm) | 기원 |
|---|---|---|---|---|
| 1 | VI | 151 | Ahrens (1952) ionic radius, | |
| 3 | IVSQ | 82 | ||
| 3 | VI | 99 | Ahrens (1952) ionic radius, | |
| 5 | VI | 71 |
동위원소 붕괴 방식 (71)
| 동위원소 | 모드 | 세기 |
|---|---|---|
| 168 | p | — |
| 169 | p | — |
| 169 | A | — |
| 169 | B+ | — |
| 170 | p | 89% |
| 170 | A | 11% |
| 171 | p | 100% |
| 171 | A | — |
| 172 | A | 100% |
| 172 | p | — |
X선 산란 인자 (506)
| 에너지 (eV) | f₁ | f₂ |
|---|---|---|
| 10 | — | 1.73645 |
| 10.1617 | — | 1.81425 |
| 10.3261 | — | 1.89553 |
| 10.4931 | — | 1.98045 |
| 10.6628 | — | 2.06919 |
| 10.8353 | — | 2.16029 |
| 11.0106 | — | 2.25522 |
| 11.1886 | — | 2.35433 |
| 11.3696 | — | 2.45698 |
| 11.5535 | — | 2.56237 |
추가 데이터
Estimated Crustal Abundance
The estimated element abundance in the earth's crust.
4×10-3 milligrams per kilogram
참고 문헌 (1)
Estimated Oceanic Abundance
The estimated element abundance in the earth's oceans.
4×10-6 milligrams per liter
참고 문헌 (1)
Sources
Sources of this element.
It occurs in veins and alluvial deposits, and is often separated from rocks and other minerals by mining and panning operations. About two thirds of the world's gold output comes from South Africa, and about two thirds of the total U.S. production comes from South Dakota and Nevada. The metal is recovered from its ores by cyaniding, amalgamating, and smelting processes. Refining is also frequently done by electrolysis. Gold occurs in sea water to the extent of 0.1 to 2 mg/ton, depending on the location where the sample is taken. As yet, no method has been found for recovering gold from sea water profitably.
참고 문헌 (1)
- [6] Gold https://periodic.lanl.gov/79.shtml
참고 문헌
(9)
Data deposited in or computed by PubChem
The half-life and atomic mass data was provided by the Atomic Mass Data Center at the International Atomic Energy Agency.
Element data are cited from the Atomic weights of the elements (an IUPAC Technical Report). The IUPAC periodic table of elements can be found at https://iupac.org/what-we-do/periodic-table-of-elements/. Additional information can be found within IUPAC publication doi:10.1515/pac-2015-0703 Copyright © 2020 International Union of Pure and Applied Chemistry.
The information are cited from Pure Appl. Chem. 2018; 90(12): 1833-2092, https://doi.org/10.1515/pac-2015-0703.
Thomas Jefferson National Accelerator Facility (Jefferson Lab) is one of 17 national laboratories funded by the U.S. Department of Energy. The lab's primary mission is to conduct basic research of the atom's nucleus using the lab's unique particle accelerator, known as the Continuous Electron Beam Accelerator Facility (CEBAF). For more information visit https://www.jlab.org/
The periodic table at the LANL (Los Alamos National Laboratory) contains basic element information together with the history, source, properties, use, handling and more. The provenance data may be found from the link under the source name.
The periodic table contains NIST's critically-evaluated data on atomic properties of the elements. The provenance data that include data for atomic spectroscopy, X-ray and gamma ray, radiation dosimetry, nuclear physics, and condensed matter physics may be found from the link under the source name. Ref: https://www.nist.gov/pml/atomic-spectra-database
This section provides all form of data related to element Gold.
The element property data was retrieved from publications.