Chromium (Cr)
transition-metalSolid
मानक परमाणु भार
51.9961 uइलेक्ट्रॉन विन्यास
[Ar] 3d5 4s1गलनांक
1906.85 °Cक्वथनांक
2670.85 °Cघनत्व
7150 kg/m³ऑक्सीकरण अवस्थाएँ
−4, −2, −1, 0, +1, +2, +3, +4, +5, +6विद्युतऋणात्मकता (पॉलिंग)
1.66आयनन ऊर्जा (प्रथम)
6.76651 eVखोज का वर्ष
1797परमाणु त्रिज्या
140 pmविवरण
Chromium is a hard transition metal best known for forming adherent, protective oxide films and for giving many minerals and compounds strong colors. It occurs mainly in chromite ores and is an important alloying element in stainless and heat-resisting steels. Its chemistry spans several oxidation states, especially +3 and +6, with a sharp contrast between relatively stable Cr(III) compounds and strongly oxidizing, often toxic Cr(VI) species.
Chromium is used extensively in automobile trim as chromium metal because of its shiny finish and corrosion resistance.
The name derives from the Greek chroma for "colour", from the many coloured compounds of chromium. It was discovered in 1797 by the French chemist and pharmacist Nicolas-Louis Vauquelin, who also isolated chromium in 1798.
Chromium was discovered by Louis-Nicholas Vauquelin while experimenting with a material known as Siberian red lead, also known as the mineral crocoite (PbCrO4), in 1797. He produced chromium oxide (CrO3) by mixing crocoite with hydrochloric acid (HCl). Although he believed a method for isolating chromium didn't yet exist, Vauquelin was pleasantly surprised in 1798 to discover that he was able to obtain metallic chromium by simply heating chromium oxide in a charcoal oven. Today, chromium is primarily obtained by heating the mineral chromite (FeCr2O4) in the presence of aluminum or silicon.
From the Greek word chroma, color. Chromium is a steel-gray, lustrous, hard metal that takes a high polish. Discovered in 1797 by the Frenchman Louis Nicolas Vauquelin.
Pure chromium is a lustrous, silvery-gray metal with a high polish and a relatively high melting point. It is hard and brittle at room temperature, and its surface is rapidly passivated by a very thin oxide layer that resists further corrosion under many conditions.
The largest use of chromium is in ferrochrome for stainless steel, where chromium provides corrosion resistance by forming a passive surface film. It is also used in tool steels, superalloys, wear-resistant coatings, and hard chromium electroplating. Chromium compounds have been used in pigments, leather tanning, wood preservation, catalysts, and refractory materials, although several Cr(VI)-based uses have been restricted or replaced because of toxicity and environmental persistence.
Chromium is a blue-white metal that is hard, brittle and very corrosion resistant. Chromium can be polished to form a very shiny surface and is often plated to other metals to form a protective and attractive covering. Chromium is added to steel to harden it and to form stainless steel, a steel alloy that contains at least 10% chromium. Other chromium-steel alloys are used to make armor plate, safes, ball bearings and cutting tools.
Chromium forms many colorful compounds that have industrial uses. Lead chromate (PbCrO4), also known as chrome yellow, has been used as a yellow pigment in paints. Chromic oxide (Cr2O3), also known as chrome green, is the ninth most abundant compound in the earth's crust and is a widely used green pigment. Rubies and emeralds also owe their colors to chromium compounds. Potassium dichromate (K2Cr2O7) is used in the tanning of leather while other chromium compounds are used as mordants, materials which permanently fix dyes to fabrics. Chromium compounds are also used to anodize aluminum, a process which coats aluminum with a thick, protective layer of oxide. Chromite, chromium's primary ore, is used to make molds for the firing of bricks because of its high melting point, moderate thermal expansion and stable crystal structure.
Chromium is used to harden steel, manufacture stainless steel, and form many useful alloys. It is mostly used in plating to produce a hard, beautiful surface and to prevent corrosion. Chromium gives glass an emerald green color and is widely used as a catalyst.
The refractory industry uses chromite for forming bricks and shapes, as it has a high melting point, moderate thermal expansion, and stability of crystalline structure.
Isotopes in Earth/Planetary Science
Molecules, atoms, and ions of the stable isotopes of chromium possess slightly different physical and chemical properties, and they commonly will be fractionated during physical, chemical, and biological processes, giving rise to variations in isotopic abundances and in atomic weights. There are measureable variations in the isotopic abundances of chromium in natural terrestrial materials (Fig. IUPAC.24.1).
SiC grains are formed in very high-temperature events that occurred before the formation of the Solar System. The chemical and isotopic composition of certain elements in these grains, such as chromium, provides insights into the origin of the Solar System. The 54Cr nucleus is only produced by supernovae. Excess amounts of this isotope in the SiC grains (relative to terrestrial isotopic composition) in primitive meteorites suggest a heterogeneous distribution of 54Cr in the early Solar System and different sources of material to our Solar System [206] L. Qin, L. R. Nittler, C. M. O. D. Alexander, J. Wang, F. J. Stadermann, R. W. Carlson. Geochim. Cosmochim. Acta.75, 629 (2010).. The early solar nebula was divided into two components. One contained chromium depleted in the lighter isotopes and the other contained heavier chromium isotopes. Isotopic studies indicate these components formed a homogeneous mixture in the early Earth, but they separated during partitioning of the Earth’s core (Fig. IUPAC.24.1) [207] F. Moynier, Q. Z. Yin, E. Schauble. Science331, 1417 (2011)., [208] W. F. McDonough. Science331, 1397 (2011)..
Mobility and toxicity of chromium metal depend largely on the oxidation state of the element. Isotopes of chromium are fractionated by reduction-oxidation (redox) chemical reactions. The isotopic composition has been used to trace the origin of the element in the environment and provide information on reduction-oxidation chemical processes [209] A. S. Ellis, T. M. Johnson, T. D. Bullen. Science295, 2060 (2002)..
Isotopes in Medicine
Stable isotopes of chromium are used to investigate the metabolism of chromium (III), which is an essential nutrient. Chromium stable isotopes (53Cr and 54Cr) have been administered to patients and the relative metabolic activity of each isotope is measured to study insulin function in patients suffering from diabetes (a disease in which the body is unable to produce any or enough insulin, and/or is not able to properly use the insulin that it does produce, resulting in elevated levels of glucose in the blood) [210] H. M. Silver, M. A. Seebeck, R. M. Cowett, K. Y. Patterson, C. Veillon. J. Soc. Gynecol. Investig.4, 254 (1997).. 51Cr and 53Cr have been used to label red blood cells to determine blood volume and life-time of red blood cells in the body [210] H. M. Silver, M. A. Seebeck, R. M. Cowett, K. Y. Patterson, C. Veillon. J. Soc. Gynecol. Investig.4, 254 (1997)..
Chromium forms compounds in oxidation states from negative values in organometallic chemistry to +6, but +3 and +6 dominate common inorganic chemistry. Chromium(III) oxide, Cr₂O₃, is a stable green solid and an important pigment and refractory material. Chromium(VI) oxide, CrO₃, chromates such as potassium chromate, K₂CrO₄, and dichromates such as potassium dichromate, K₂Cr₂O₇, are strong oxidants. Chromium(II) chloride, CrCl₂, is a reducing Cr(II) salt used in specialized synthesis.
All compounds of chromium are colored. The most important chromates are those of sodium and potassium, the dichromates, and the potassium and ammonium chrome alums. The dichromates are used as oxidizing agents in quantitative analysis, also in tanning leather.
Other compounds are of industrial value; lead chromate is chrome yellow, a valued pigment. Chromium compounds are used in the textile industry as mordants, and by the aircraft and other industries for anodizing aluminum.
See more information at the Chromium compound page.
Metallic chromium is not highly reactive in bulk form, but dusts and fumes from welding, grinding, or plating operations can be hazardous. Soluble Cr(VI) compounds are toxic, corrosive, sensitizing, and carcinogenic by inhalation, and they require strict exposure control. Cr(III) compounds are generally less mobile and less toxic, although concentrated salts and fine powders still present chemical and occupational hazards.
Chromium compounds are toxic and should be handled with proper safeguards.
Chromium is a natural trace constituent of rocks, soils, and sediments, commonly associated with ultramafic rocks and chromite minerals. In the environment, Cr(III) tends to form insoluble hydroxides and complexes with organic matter, while Cr(VI) oxyanions are more mobile in oxygenated waters. Industrial releases from plating, tanning, pigment manufacture, and waste disposal have produced localized contamination where redox conditions control persistence and transport.
Chromium is produced chiefly by mining chromite ore and reducing it to ferrochrome for steelmaking. South Africa, Kazakhstan, India, Turkey, and several other countries are important sources of chromite, so supply is tied to ore quality, energy costs, and metallurgical capacity. Demand is dominated by stainless steel production, with smaller markets for chemicals, refractories, and plating. Recycling occurs mainly through stainless steel and alloy scrap, which returns chromium to steel production and reduces dependence on primary ore.
The principal ore is chromite, which is found in Zimbabwe, Russia, New Zealand, Turkey, Iran, Albania, Finland, Democratic Republic of Madagascar, and the Phillippines. The metal is usually produced by reducing the oxide with aluminum.
Chromium is a minor but widespread element in the cosmos, made mainly in massive stars and supernova nucleosynthesis near the iron peak. It is present in the Sun, meteorites, and rocky planetary materials. Isotopic ratios of chromium in meteorites are used in cosmochemistry to trace early Solar System reservoirs and nucleosynthetic contributions.
- The name chromium comes from the Greek word for color, reflecting its vividly colored compounds.
- Ruby owes its red color to trace Cr³⁺ substituting for aluminum in corundum.
- Chrome plating can be decorative, but engineering hard chrome is used mainly for wear resistance.
- Passivation by chromium oxide is the key reason stainless steel does not behave like ordinary carbon steel.
- Lead chromate, PbCrO₄, was once a major yellow pigment but is now restricted in many applications.
- Chromium metal is usually traded through ferrochrome rather than as pure metal.
चित्र
गुण
भौतिक
- परमाणु त्रिज्या (आनुभविक)
- 140 pm सभी तत्वों की परमाणु त्रिज्या (आनुभविक) की तुलना करें →
- सहसंयोजक त्रिज्या
- 139 pm सभी तत्वों की सहसंयोजक त्रिज्या की तुलना करें →
- वान डर वाल्स त्रिज्या
- 189 pm सभी तत्वों की वान डर वाल्स त्रिज्या की तुलना करें →
- धात्विक त्रिज्या
- 119 pm सभी तत्वों की धात्विक त्रिज्या की तुलना करें →
- घनत्व
- 7150 kg/m³ सभी तत्वों की घनत्व की तुलना करें →
- मोलर आयतन
- 0.00723 L/mol
- STP पर प्रावस्था
- ठोस सभी तत्वों की STP पर प्रावस्था की तुलना करें →
- गलनांक
- 1906.85 °C सभी तत्वों की गलनांक की तुलना करें →
- क्वथनांक
- 2670.85 °C सभी तत्वों की क्वथनांक की तुलना करें →
- तापीय चालकता
- 93.9 W/(m·K) सभी तत्वों की तापीय चालकता की तुलना करें →
- विशिष्ट ऊष्मा धारिता
- 0.449 J/(g·K) सभी तत्वों की विशिष्ट ऊष्मा धारिता की तुलना करें →
- मोलर ऊष्मा धारिता
- 23.35 J/(mol·K) सभी तत्वों की मोलर ऊष्मा धारिता की तुलना करें →
- क्रिस्टल संरचना
- अंतःकेंद्रित घनीय सभी तत्वों की क्रिस्टल संरचना की तुलना करें →
रासायनिक
- विद्युतऋणात्मकता (पॉलिंग)
- 1.66 सभी तत्वों की विद्युतऋणात्मकता (पॉलिंग) की तुलना करें →
- विद्युतऋणात्मकता (ऐलन)
- 1.65
- इलेक्ट्रॉन बंधुता
- 0.675 eV
- आयनन ऊर्जा (प्रथम)
- 6.76651 eV सभी तत्वों की आयनन ऊर्जा (प्रथम) की तुलना करें →
- आयनन ऊर्जा (द्वितीय)
- 16.486362 eV सभी तत्वों की आयनन ऊर्जा (द्वितीय) की तुलना करें →
- आयनन ऊर्जा (तृतीय)
- 30.959107 eV सभी तत्वों की आयनन ऊर्जा (तृतीय) की तुलना करें →
- आयनन ऊर्जा (चतुर्थ)
- 49.160169 eV सभी तत्वों की आयनन ऊर्जा (चतुर्थ) की तुलना करें →
- आयनन ऊर्जा (पंचम)
- 69.460239 eV सभी तत्वों की आयनन ऊर्जा (पंचम) की तुलना करें →
- ऑक्सीकरण अवस्थाएँ
- −4, −2, −1, 0, +1, +2, +3, +4, +5, +6 सभी तत्वों की ऑक्सीकरण अवस्थाएँ की तुलना करें →
- संयोजकता इलेक्ट्रॉन
- 6 सभी तत्वों की संयोजकता इलेक्ट्रॉन की तुलना करें →
- इलेक्ट्रॉन विन्यास
- [Ar] 3d5 4s1
ऊष्मागतिक
- गलन ऊष्मा
- 0.21246826 eV सभी तत्वों की गलन ऊष्मा की तुलना करें →
- वाष्पन ऊष्मा
- 3.518682 eV सभी तत्वों की वाष्पन ऊष्मा की तुलना करें →
- ऊर्ध्वपातन ऊष्मा
- 4.119811 eV
- परमाणुकरण ऊष्मा
- 4.119811 eV
- परमाणुकरण एन्थैल्पी
- 4.119604 eV
नाभिकीय
- प्रोटॉन
- 24 सभी तत्वों की प्रोटॉन की तुलना करें →
- न्यूट्रॉन
- 28 सभी तत्वों की न्यूट्रॉन की तुलना करें →
- ज्ञात समस्थानिक
- 30 सभी तत्वों की ज्ञात समस्थानिक की तुलना करें →
- स्थिर समस्थानिक
- 3 सभी तत्वों की स्थिर समस्थानिक की तुलना करें →
- सबसे स्थिर समस्थानिक
- Cr-52
- खोज का वर्ष
- 1797
प्रचुरता
- प्रचुरता (भूपर्पटी)
- 102 mg/kg सभी तत्वों की प्रचुरता (भूपर्पटी) की तुलना करें →
- प्रचुरता (महासागर)
- 3 × 10−4 mg/L सभी तत्वों की प्रचुरता (महासागर) की तुलना करें →
क्रिस्टल संरचना
- जालक स्थिरांक a
- 288 pm
इलेक्ट्रॉनिक संरचना
- प्रति कोश इलेक्ट्रॉन
- 2, 8, 13, 1 सभी तत्वों की प्रति कोश इलेक्ट्रॉन की तुलना करें →
पहचानकर्ता
- CAS संख्या
- 7440-47-3 सभी तत्वों की CAS संख्या की तुलना करें →
- टर्म प्रतीक
- 7S3
- InChI
- InChI=1S/Cr
- InChI कुंजी
- VYZAMTAEIAYCRO-UHFFFAOYSA-N
इलेक्ट्रॉन विन्यास मापित
Cr: 3d⁵ 4s¹[Ar] 3d⁵ 4s¹1s² 2s² 2p⁶ 3s² 3p⁶ 3d⁵ 4s¹परमाणु मॉडल
समस्थानिक न्यूट्रॉन की संख्या, द्रव्यमान और स्थिरता बदलते हैं — उदासीन परमाणु का इलेक्ट्रॉन विन्यास नहीं।
सांकेतिक परमाणु मॉडल, वास्तविक अनुपात में नहीं।
परमाणु पहचान-चिह्न
उत्सर्जन / अवशोषण स्पेक्ट्रम
समस्थानिक वितरण
| द्रव्यमान संख्या | परमाणु द्रव्यमान (u) | प्राकृतिक प्रचुरता | अर्धायु |
|---|---|---|---|
| 52 स्थिर | 51.94050623 ± 0.00000063 | 83.7890% | स्थिर |
| 53 स्थिर | 52.94064815 ± 0.00000062 | 9.5010% | स्थिर |
| 54 स्थिर | 53.93887916 ± 0.00000061 | 2.3650% | स्थिर |
प्रावस्था / अवस्था
कारण: गलनांक (1906.85 °C) से 1881.8 °C कम
सांकेतिक, वास्तविक अनुपात में नहीं
प्रावस्था संक्रमण बिंदु
संक्रमण ऊर्जाएँ
गलनांक पर 1 mol को पिघलाने के लिए आवश्यक ऊर्जा
क्वथनांक पर 1 mol को वाष्पित करने के लिए आवश्यक ऊर्जा
ऊर्ध्वपातनांक पर 1 mol के ऊर्ध्वपातन के लिए आवश्यक ऊर्जा
घनत्व
मानक परिस्थितियों में
मानक परिस्थितियों में
परमाणु स्पेक्ट्रम
24 में से 10 दिखाए जा रहे हैं। आयन के आवेश के अनुसार आरोही क्रम में व्यवस्थित।
उपलब्ध स्पेक्ट्रमी रेखा डेटा ?
| आयन | आवेश | कुल रेखाएँ | संक्रमण प्रायिकताएँ | स्तर पदनाम |
|---|---|---|---|---|
| Cr I | 0 | 4369 | 527 | 4369 |
| Cr II | +1 | 5370 | 92 | 5370 |
| Cr III | +2 | 136 | 0 | 0 |
| Cr IV | +3 | 188 | 102 | 102 |
| Cr V | +4 | 193 | 104 | 193 |
| Cr VI | +5 | 102 | 26 | 102 |
| Cr VII | +6 | 143 | 4 | 143 |
| Cr VIII | +7 | 36 | 9 | 36 |
| Cr IX | +8 | 58 | 18 | 58 |
| Cr X | +9 | 75 | 46 | 75 |
उपलब्ध ऊर्जा स्तर डेटा ?
| आयन | आवेश | स्तर |
|---|---|---|
| Cr I | 0 | 659 |
| Cr II | +1 | 914 |
| Cr III | +2 | 215 |
| Cr IV | +3 | 155 |
| Cr V | +4 | 47 |
| Cr VI | +5 | 63 |
| Cr VII | +6 | 66 |
| Cr VIII | +7 | 34 |
| Cr IX | +8 | 49 |
| Cr X | +9 | 39 |
आयनिक त्रिज्याएँ
| आवेश | उपसहसंयोजन | प्रचक्रण | त्रिज्या |
|---|---|---|---|
| +2 | 6 | low | 73 pm |
| +2 | 6 | high | 80 pm |
| +3 | 6 | उपलब्ध नहीं | 61.5 pm |
| +4 | 4 | उपलब्ध नहीं | 41 pm |
| +4 | 6 | उपलब्ध नहीं | 55.00000000000001 pm |
| +5 | 4 | उपलब्ध नहीं | 34.5 pm |
| +5 | 6 | उपलब्ध नहीं | 49 pm |
| +5 | 8 | उपलब्ध नहीं | 56.99999999999999 pm |
| +6 | 4 | उपलब्ध नहीं | 26 pm |
| +6 | 6 | उपलब्ध नहीं | 44 pm |
यौगिक
समस्थानिक (3)
| द्रव्यमान संख्या | परमाणु द्रव्यमान (u) | प्राकृतिक प्रचुरता | अर्धायु | क्षय का प्रकार | |
|---|---|---|---|---|---|
| 52 स्थिर | 51.94050623 ± 0.00000063 | 83.7890% ± 0.0180% | स्थिर | stable | |
| 53 स्थिर | 52.94064815 ± 0.00000062 | 9.5010% ± 0.0170% | स्थिर | stable | |
| 54 स्थिर | 53.93887916 ± 0.00000061 | 2.3650% ± 0.0070% | स्थिर | stable |
स्पेक्ट्रमी रेखाएँ
2531 में से 50 दिखाए जा रहे हैं। डिफ़ॉल्ट रूप से केवल मापित तीव्रता वाली स्पेक्ट्रमी रेखाएँ दिखाई जाती हैं।
| तरंगदैर्घ्य (nm) | तीव्रता | आयनन अवस्था | प्रकार | संक्रमण | सटीकता | स्रोत | |
|---|---|---|---|---|---|---|---|
| 540.978408 nm | 8500 | Cr I | emission | 3d4.4s2 a 5D → 3d5.(6S).4p z 5P* | मापित | NIST | |
| 534.57965 nm | 5100 | Cr I | emission | 3d4.4s2 a 5D → 3d5.(6S).4p z 5P* | मापित | NIST | |
| 529.827202 nm | 3540 | Cr I | emission | 3d4.4s2 a 5D → 3d5.(6S).4p z 5P* | मापित | NIST | |
| 435.17622 nm | 3500 | Cr I | emission | 3d4.4s2 a 5D → 3d4.(5D).4s.4p.(3P*) z 5F* | मापित | NIST | |
| 534.83147 nm | 3200 | Cr I | emission | 3d4.4s2 a 5D → 3d5.(6S).4p z 5P* | मापित | NIST | |
| 434.450128 nm | 3100 | Cr I | emission | 3d4.4s2 a 5D → 3d4.(5D).4s.4p.(3P*) z 5F* | मापित | NIST | |
| 433.944609 nm | 2600 | Cr I | emission | 3d4.4s2 a 5D → 3d4.(5D).4s.4p.(3P*) z 5F* | मापित | NIST | |
| 526.415341 nm | 2600 | Cr I | emission | 3d4.4s2 a 5D → 3d5.(6S).4p z 5P* | मापित | NIST | |
| 464.616212 nm | 2400 | Cr I | emission | 3d4.4s2 a 5D → 3d4.(5D).4s.4p.(3P*) y 5P* | मापित | NIST | |
| 529.669109 nm | 2100 | Cr I | emission | 3d4.4s2 a 5D → 3d5.(6S).4p z 5P* | मापित | NIST | |
| 391.915844 nm | 2030 | Cr I | emission | 3d4.4s2 a 5D → 3d4.(5D).4s.4p.(3P*) z 5D* | मापित | NIST | |
| 433.755701 nm | 1900 | Cr I | emission | 3d4.4s2 a 5D → 3d4.(5D).4s.4p.(3P*) z 5F* | मापित | NIST | |
| 740.01798 nm | 1900 | Cr I | emission | 3d5.(6S).4p z 7P* → 3d5.(6S).5s e 7S | मापित | NIST | |
| 465.215743 nm | 1750 | Cr I | emission | 3d4.4s2 a 5D → 3d4.(5D).4s.4p.(3P*) y 5P* | मापित | NIST | |
| 435.962444 nm | 1420 | Cr I | emission | 3d4.4s2 a 5D → 3d4.(5D).4s.4p.(3P*) z 5F* | मापित | NIST | |
| 437.127465 nm | 1400 | Cr I | emission | 3d4.4s2 a 5D → 3d4.(5D).4s.4p.(3P*) z 5F* | मापित | NIST | |
| 735.58903 nm | 1400 | Cr I | emission | 3d5.(6S).4p z 7P* → 3d5.(6S).5s e 7S | मापित | NIST | |
| 461.612404 nm | 1360 | Cr I | emission | 3d4.4s2 a 5D → 3d4.(5D).4s.4p.(3P*) y 5P* | मापित | NIST | |
| 390.875593 nm | 1310 | Cr I | emission | 3d4.4s2 a 5D → 3d4.(5D).4s.4p.(3P*) z 5D* | मापित | NIST | |
| 449.685195 nm | 1300 | Cr I | emission | 3d5.(6S).4s a 5S → 3d4.(5D).4s.4p.(3P*) y 5P* | मापित | NIST | |
| 524.756509 nm | 1250 | Cr I | emission | 3d4.4s2 a 5D → 3d5.(6S).4p z 5P* | मापित | NIST | |
| 460.074835 nm | 1190 | Cr I | emission | 3d4.4s2 a 5D → 3d4.(5D).4s.4p.(3P*) y 5P* | मापित | NIST | |
| 433.971051 nm | 1120 | Cr I | emission | 3d4.4s2 a 5D → 3d4.(5D).4s.4p.(3P*) z 5F* | मापित | NIST | |
| 462.617342 nm | 1100 | Cr I | emission | 3d4.4s2 a 5D → 3d4.(5D).4s.4p.(3P*) y 5P* | मापित | NIST | |
| 435.104951 nm | 1080 | Cr I | emission | 3d4.4s2 a 5D → 3d4.(5D).4s.4p.(3P*) z 5F* | मापित | NIST | |
| 438.4975 nm | 1060 | Cr I | emission | 3d4.4s2 a 5D → 3d4.(5D).4s.4p.(3P*) z 5F* | मापित | NIST | |
| 526.571497 nm | 1050 | Cr I | emission | 3d4.4s2 a 5D → 3d5.(6S).4p z 5P* | मापित | NIST | |
| 452.64538 nm | 960 | Cr I | emission | 3d5.(4G).4s a 5G → 3d5.(4G).4p z 5G* | मापित | NIST | |
| 454.595302 nm | 930 | Cr I | emission | 3d5.(6S).4s a 5S → 3d4.(5D).4s.4p.(3P*) y 5P* | मापित | NIST | |
| 532.832346 nm | 930 | Cr I | emission | 3d5.(6S).4p z 7P* → 3d5.(6S).4d e 7D | मापित | NIST | |
| 388.32867 nm | 910 | Cr I | emission | 3d4.4s2 a 5D → 3d4.(5D).4s.4p.(3P*) z 5D* | मापित | NIST | |
| 392.86372 nm | 880 | Cr I | emission | 3d4.4s2 a 5D → 3d4.(5D).4s.4p.(3P*) z 5D* | मापित | NIST | |
| 388.521354 nm | 810 | Cr I | emission | 3d4.4s2 a 5D → 3d4.(5D).4s.4p.(3P*) z 5D* | मापित | NIST | |
| 746.23079 nm | 800 | Cr I | emission | 3d5.(6S).4p z 7P* → 3d5.(6S).5s e 7S | मापित | NIST | |
| 453.073802 nm | 770 | Cr I | emission | 3d5.(4G).4s a 5G → 3d5.(4G).4p z 5G* | मापित | NIST | |
| 388.679508 nm | 740 | Cr I | emission | 3d4.4s2 a 5D → 3d4.(5D).4s.4p.(3P*) z 5D* | मापित | NIST | |
| 392.102067 nm | 740 | Cr I | emission | 3d4.4s2 a 5D → 3d4.(5D).4s.4p.(3P*) z 5D* | मापित | NIST | |
| 394.148757 nm | 720 | Cr I | emission | 3d4.4s2 a 5D → 3d4.(5D).4s.4p.(3P*) z 5D* | मापित | NIST | |
| 697.83983 nm | 640 | Cr I | emission | 3d4.(5D).4s.4p.(3P*) y 7P* → 3d5.(6S).4d e 7D | मापित | NIST | |
| 396.3684 nm | 620 | Cr I | emission | 3d5.(4G).4s a 5G → 3d5.(4G).4p y 5H* | मापित | NIST | |
| 453.569676 nm | 600 | Cr I | emission | 3d5.(4G).4s a 5G → 3d5.(4G).4p z 5G* | मापित | NIST | |
| 390.290908 nm | 590 | Cr I | emission | 3d4.4s2 a 5D → 3d4.(5D).4s.4p.(3P*) z 5D* | मापित | NIST | |
| 455.864413 nm | 590 | Cr II | emission | 3d5 b 4F → 3d4.(5D).4p z 4D* | मापित | NIST | |
| 461.335727 nm | 590 | Cr I | emission | 3d4.4s2 a 5D → 3d4.(5D).4s.4p.(3P*) y 5P* | मापित | NIST | |
| 396.974253 nm | 570 | Cr I | emission | 3d5.(4G).4s a 5G → 3d5.(4G).4p y 5H* | मापित | NIST | |
| 458.004789 nm | 560 | Cr I | emission | 3d5.(6S).4s a 5S → 3d4.(5D).4s.4p.(3P*) y 5P* | मापित | NIST | |
| 530.074563 nm | 530 | Cr I | emission | 3d4.4s2 a 5D → 3d5.(6S).4p z 5P* | मापित | NIST | |
| 397.665859 nm | 520 | Cr I | emission | 3d5.(4G).4s a 5G → 3d5.(4G).4p y 5H* | मापित | NIST | |
| 454.04987 nm | 500 | Cr I | emission | 3d5.(4G).4s a 5G → 3d5.(4G).4p z 5G* | मापित | NIST | |
| 459.139098 nm | 490 | Cr I | emission | 3d4.4s2 a 5D → 3d4.(5D).4s.4p.(3P*) y 5P* | मापित | NIST |
विस्तृत गुण
सहसंयोजक त्रिज्याएँ (विस्तृत)
- सहसंयोजक त्रिज्या (प्यूक्को)
- 122 pm
- सहसंयोजक त्रिज्या (प्यूक्को, द्विबंध)
- 111 pm
- सहसंयोजक त्रिज्या (प्यूक्को, त्रिबंध)
- 103 pm
- सहसंयोजक त्रिज्या (ब्रैग)
- 140 pm
वान डर वाल्स त्रिज्याएँ
- Batsanov
- 205 pm
- Alvarez
- 245 pm
- UFF
- 302.3 pm
- MM3
- 225 pm
परमाणु और धात्विक त्रिज्याएँ
- परमाणु त्रिज्या (राह्म)
- 233 pm
- धात्विक त्रिज्या (C12)
- 128 pm
संख्यांकन मापक्रम
- Mendeleev
- 51
- Pettifor
- 57
- Glawe
- 55
विद्युतऋणात्मकता मापक्रम
- Ghosh
- 0
- Miedema
- 5
- Gunnarsson–Lundqvist
- 4
- Robles–Bartolotti
- 2
ध्रुवणीयता और परिक्षेपण
- द्विध्रुव ध्रुवणीयता
- 83 a.u.
- द्विध्रुव ध्रुवणीयता (अनिश्चितता)
- 12 a.u.
- C₆
- 602 Ha·Bohr6
- C₆ (Gould–Bučko)
- 709 Ha·Bohr6
रासायनिक बंधुता
- प्रोटॉन बंधुता
- 791.3 kJ/mol
- गैसीय क्षारकता
- 768.4 kJ/mol
मीडेमा प्राचल
- मीडेमा मोलर आयतन
- 7.23 cm3/mol
- मीडेमा इलेक्ट्रॉन घनत्व
- 5
आपूर्ति जोखिम और अर्थशास्त्र
- उत्पादन संकेंद्रण
- 37
- सापेक्ष आपूर्ति जोखिम
- 6
- भंडार वितरण
- 46
- राजनीतिक स्थिरता (प्रमुख उत्पादक)
- 44
- राजनीतिक स्थिरता (सबसे अधिक भंडार वाला देश)
- 62
प्रावस्था संक्रमण और अपररूप
| गलनांक | 2180.15 K |
| क्वथनांक | 2944.15 K |
ऑक्सीकरण अवस्था की श्रेणियाँ
उन्नत संदर्भ डेटा
परिरक्षण स्थिरांक (7)
| n | कक्षक | σ |
|---|---|---|
| 1 | s | 0.5862 |
| 2 | p | 3.9248 |
| 2 | s | 7.0162 |
| 3 | d | 14.2434 |
| 3 | p | 12.534 |
| 3 | s | 11.6322 |
| 4 | s | 18.8668 |
क्रिस्टल त्रिज्याओं का विवरण (10)
| आवेश | CN | प्रचक्रण | rcrystal (pm) | उत्पत्ति |
|---|---|---|---|---|
| 2 | VI | LS | 87 | estimated, |
| 2 | VI | HS | 94 | from r^3 vs V plots, |
| 3 | VI | 75.5 | from r^3 vs V plots, | |
| 4 | IV | 55 | ||
| 4 | VI | 69 | from r^3 vs V plots, | |
| 5 | IV | 48.5 | from r^3 vs V plots, | |
| 5 | VI | 63 | estimated, from r^3 vs V plots, | |
| 5 | VIII | 71 | ||
| 6 | IV | 40 | ||
| 6 | VI | 58 | calculated, |
समस्थानिक क्षय के प्रकार (52)
| समस्थानिक | मोड | तीव्रता |
|---|---|---|
| 41 | p | — |
| 42 | B+ | 100% |
| 42 | B+p | 94.4% |
| 42 | 2p | — |
| 43 | B+ | 100% |
| 43 | B+p | 79.3% |
| 43 | 2p | 11.6% |
| 43 | 3p | 0.1% |
| 43 | B+A | — |
| 44 | B+ | 100% |
एक्स-रे प्रकीर्णन गुणक (751)
| ऊर्जा (eV) | f₁ | f₂ |
|---|---|---|
| 0.42 | -0.0076 | 0.02756 |
| 0.46 | -0.01 | 0.03022 |
| 0.5 | -0.0123 | 0.03301 |
| 0.54 | -0.0148 | 0.03586 |
| 0.58 | -0.0176 | 0.03897 |
| 0.62 | -0.0202 | 0.04225 |
| 0.66 | -0.0225 | 0.04515 |
| 0.7 | -0.0257 | 0.04771 |
| 0.74 | -0.0292 | 0.05056 |
| 0.78 | -0.0332 | 0.05331 |
अतिरिक्त डेटा
Estimated Crustal Abundance
The estimated element abundance in the earth's crust.
1.02×102 milligrams per kilogram
संदर्भ (1)
- [5] Chromium https://education.jlab.org/itselemental/ele024.html
Estimated Oceanic Abundance
The estimated element abundance in the earth's oceans.
3×10-4 milligrams per liter
संदर्भ (1)
- [5] Chromium https://education.jlab.org/itselemental/ele024.html
Sources
Sources of this element.
The principal ore is chromite, which is found in Zimbabwe, Russia, New Zealand, Turkey, Iran, Albania, Finland, Democratic Republic of Madagascar, and the Phillippines. The metal is usually produced by reducing the oxide with aluminum.
संदर्भ (1)
- [6] Chromium https://periodic.lanl.gov/24.shtml
संदर्भ
(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 Chromium.
The element property data was retrieved from publications.