Calcium (Ca)
alkaline-earth-metalSolid
Masse atomique relative standard
40,078 uConfiguration électronique
[Ar] 4s2Point de fusion
841,85 °CPoint d’ébullition
1483,85 °CMasse volumique
1540 kg/m³États d’oxydation
+1, +2Électronégativité (Pauling)
1Énergie d’ionisation (1re)
6,113155 eVAnnée de découverte
1808Rayon atomique
180 pmDétails
Calcium is an alkaline earth metal and the fifth most abundant element in Earth’s crust by mass. It is highly reactive as a free metal but widespread in stable minerals, especially carbonates, sulfates, phosphates, and silicates. Calcium chemistry is dominated by the Ca²⁺ ion, which is hard, strongly hydrated, and central to limestone formation, cement chemistry, seawater buffering, bones, teeth, shells, and many cellular signaling processes.
The metal has a silvery color, is rather hard, and is prepared by electrolysis of fused chloride and calcium fluoride (to lower the melting point).
Chemically it is one of the alkaline earth elements; it readily forms a white coating of nitride in air, reacts with water, burns with a yellow-red flame.
The name derives from the Latin calx for "lime" (CaO) or "limestone" (CaCO3) in which it was found. It was first isolated by British chemist Humphry Davy in 1808 with help from the Swedish chemist Jöns Jacob Berzelius and the Swedish court physician M. M. af Pontin.
Although calcium is the fifth most abundant element in the earth's crust, it is never found free in nature since it easily forms compounds by reacting with oxygen and water. Metallic calcium was first isolated by Sir Humphry Davy in 1808 through the electrolysis of a mixture of lime (CaO) and mercuric oxide (HgO). Today, metallic calcium is obtained by displacing calcium atoms in lime with atoms of aluminum in hot, low-pressure containers. About 4.2% of the earth's crust is composed of calcium.
From the Latin word calx, lime. Though lime was prepared by the Romans in the first century under the name calx, the metal was not discovered until 1808. After learning that Berzelius and Pontin prepared calcium amalgam by electrolyzing lime in mercury, Davy was able to isolate the impure metal.
Pure calcium is a silvery gray metal that is softer than many structural metals and can be cut when freshly prepared. It tarnishes in air as oxide, nitride, and hydroxide films form, and it reacts slowly with water, releasing H₂. It is normally stored protected from moisture and air.
Metallic calcium is used on a modest scale as a reducing agent, deoxidizer, desulfurizer, and alloying additive, especially in specialty metallurgy and in some lead and aluminum alloys. Much larger practical use is tied to calcium-containing materials: limestone, lime, gypsum, and calcium silicates are essential in cement, glass, steelmaking fluxes, soil amendment, water treatment, and construction. Calcium compounds are also used in food, pharmaceuticals, paper, plastics, and flue-gas treatment.
Due to its high reactivity with common materials, there is very little demand for metallic calcium. It is used in some chemical processes to refine thorium, uranium and zirconium. Calcium is also used to remove oxygen, sulfur and carbon from certain alloys. Calcium can be alloyed with aluminum, beryllium, copper, lead and magnesium. Calcium is also used in vacuum tubes as a getter, a material that combines with and removes trace gases from vacuum tubes.
Calcium carbonate (CaCO3) is one of the common compounds of calcium. It is heated to form quicklime (CaO) which is then added to water (H2O). This forms another material known as slaked lime (Ca(OH)2) which is an inexpensive base material used throughout the chemical industry. Chalk, marble and limestone are all forms of calcium carbonate. Calcium carbonate is used to make white paint, cleaning powder, toothpaste and stomach antacids, among other things. Other common compounds of calcium include: calcium sulfate (CaSO4), also known as gypsum, which is used to make dry wall and plaster of Paris, calcium nitrate (Ca(NO3)2), a naturally occurring fertilizer and calcium phosphate (Ca3(PO4)2), the main material found in bones and teeth.
The metal is used as a reducing agent in preparing other metals such as thorium, uranium, zirconium, etc., and is used as a deoxidizer, desulfurizer, or decarburizer for various ferrous and nonferrous alloys. It is also used as an alloying agent for aluminum, beryllium, copper, lead, and magnesium alloys, and serves as a "getter" for residual gases in vacuum tubes, etc.
Isotopes in Earth/Planetary Science
Molecules, atoms, and ions of the stable isotopes of calcium 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 (Fig. IUPAC.20.1). The isotope-amount ratio n(44Ca)/n(40Ca) is used to quantify the calcium cycle (sources and sinks of calcium) in the ocean. Calcium isotopes fractionate (separate) in terrestrial and marine environments owing to biological and inorganic processes, which discriminate against heavy calcium isotopes. The calcification process controls the removal of calcium from the ocean, which is mostly balanced by hydrothermal and riverine calcium input. Calcium has a long residence time, symbol τ, in seawater (τCa about 1 to 2 million years) relative to the short mixing time of the global ocean (about 1000 years), which has allowed the calcium isotopic composition of modern seawater to homogenize globally. This was likely the case in the geological past as well, which makes the n(44Ca)/n(40Ca) ratio useful when quantifying the oceanic calcium cycle [182] P. Zhu, J. D. Macdougall. Geochim. Cosmochim. Acta62, 1691 (1998)., [183] J. Farkaš, D. Buhl, J. Blenkinsop, J. Veizer. Earth Planet. Sci. Lett.253, 96 (2007).. The isotope-amount ratio n(44Ca)/n(40Ca) has been used to trace sources of calcium in soil and river water [184] T. Walczyk. Fresenius J. Anal. Chem.370, 444 (2001).. The isotope-amount ratio n(44Ca)/n(40Ca) ratio of calcium carbonate may serve as a paleothermometer to determine seawater temperatures in the past, making use of the temperature-dependent isotopic fractionation between 40Ca and 44Ca [185] E. M. Griffith, E. A. Schauble, T. D. Bullen, A. Paytan. Geochim. Cosmochim. Acta72, 5641 (2008)., [186] T. F. Nägler, A. Eisenhauer, A. Müller, C. Hemleben, J. Kramers. Geochem. Geophy. Geosy.1, 1052 (2000)..
The radioactive isotope 45Ca (half-life of 163 days) is used to study calcium behavior in soils, detergents, water-purification systems, and glassy materials. 45Ca is introduced into a system and monitored to measure various types of calcium responses within the system and to investigate how calcium of one matrix may interact with another (i.e. calcium of soil mixing with that of fertilizers). 45Ca has been used to investigate the transport of contaminants in groundwater through the unsaturated zone [187] P. Nkedi-Kizza, M. L. Brusseau, P. S. C. Rao, A. G. Hornsby. Environ. Sci. Technol.23, 814 (1989)..
Isotopes in Medicine
Stable isotopes of calcium (42Ca, 44Ca, 46Ca, and 48Ca) and radioisotopes of calcium (45Ca and 47Ca, with a half-life of 109 h) can be used for tracing calcium uptake, utilization, and excretion in the body. For example, most of our knowledge on the efficiency by which calcium is absorbed in the intestine (bioavailability) comes from studies in which calcium in the diet was labeled with stable or radioactive isotopes. In such studies, the isotope-labeled food is ingested and fecal matter tested for the presence and quantity of unabsorbed isotope. When coupling oral ingestion of food labeled with one calcium isotope with an intravenous injection of a second calcium isotope, this technique can be used as a means to measure calcium absorption within the body by measuring excretion of both tracers in the urine. In a similar fashion, dietary absorption of magnesium and zinc can be studied [184] T. Walczyk. Fresenius J. Anal. Chem.370, 444 (2001)., [188] S. J. Adelstein, F. J. Manning. Isotopes for Medicine and the Life Sciences, pp. 20–25, National Academy Press, Washington DC (1995)..
Stable and radioactive isotopes are used in biomedical research and clinical practice to study disorders associated with calcium metabolism, in particular in relation to bone health and calcium accumulation in body tissues (vascular calcification, kidney stone formation). Stable isotope tracers have been used successfully to study bone calcium balance during space-flight and in-bed-rest studies. A long-living calcium radioisotope (41Ca), with a half-life of 9.9×104 years, has been used successfully for labeling of bone calcium to measure bone calcium turnover via urinary excretion of the tracer [189] D. Elmore, M. H. Bhattacharyya, N. Sacco-Gibson, D. P. Peterson. Nucl. Instrum. Methods Phys. Res. Sect. B52, 531 (1990)..
Calcium nearly always occurs in the +2 oxidation state, forming ionic or partly ionic compounds with high lattice energies. Important minerals and materials include calcium carbonate (CaCO₃), calcium sulfate dihydrate (CaSO₄·2H₂O), calcium oxide (CaO), calcium hydroxide (Ca(OH)₂), calcium chloride (CaCl₂), and calcium phosphate phases such as hydroxyapatite (Ca₅(PO₄)₃OH). Calcium hydride (CaH₂) is a useful drying and hydrogen-generating reagent. Calcium forms organometallic reagents, but they are less common than magnesium analogues.
Its natural and prepared compounds are widely used. Quicklime (CaO), which is made by heating limestone that is changed into slaked lime by carefully adding water, is the great base of chemical refinery with countless uses.
When mixed with sand, it hardens mortar and plaster by taking up carbon dioxide from the air. Calcium from limestone is an important element in Portland cement.
Solubility of the carbonate in water containing carbon dioxide is high, which causes the formation of caves with stalactites and stalagmites and is responsible for hardness in water. Other important compounds are the carbide, chloride, cyanamide, hypochlorite, nitrate, and sulfide.
See more information at the Calcium compound page.
Calcium is an essential nutrient, but concentrated calcium metal and many reactive calcium compounds require care. The metal reacts with water and acids to produce flammable H₂ and caustic solutions. Calcium oxide (CaO) and calcium hydroxide (Ca(OH)₂) are strongly alkaline and can burn skin, eyes, and respiratory tissue. Soluble calcium salts are generally of low acute toxicity, although excessive intake or exposure can disturb normal mineral balance. Dust from limestone, cement, or gypsum is mainly a particulate and alkalinity hazard.
Calcium is a major participant in the rock, water, and biological cycles. Weathering releases Ca²⁺ from silicate and carbonate minerals, rivers carry it to lakes and oceans, and it is removed by carbonate precipitation, shell formation, and sedimentation. Calcium affects soil structure and pH buffering and is an essential macronutrient for plants and animals. Acid deposition can leach calcium from soils and alter forest and freshwater ecosystems.
The calcium economy is dominated not by the metal but by abundant minerals and processed materials. Limestone and gypsum are quarried on large scales, while lime is produced by heating calcium carbonate (CaCO₃) to make calcium oxide (CaO). Portland cement production consumes major quantities of calcium-rich feedstocks. Metallic calcium is a smaller specialty product, commonly made by electrolysis or metallothermic reduction routes and used where its strong reducing and scavenging properties justify handling costs. Recycling is indirect, mainly through construction materials, steel slags, and industrial by-products rather than recovery of elemental calcium.
Calcium, a metallic element, is fifth in abundance in the earth's crust, of which it forms more than 3%. It is an essential constituent of leaves, bones, teeth, and shells. Never found in nature uncombined, it occurs abundantly as limestone, gypsum, and fluorite. Apatite is the fluorophosphate or chlorophosphate of calcium.
Calcium is a common cosmic element produced chiefly in massive stars during advanced nuclear burning and dispersed by supernovae. Its spectral lines are prominent in many stars and in interstellar gas. In rocky planets it is concentrated into silicate and carbonate minerals, while in meteorites it occurs in calcium-aluminum-rich inclusions that record very early high-temperature solids in the Solar System.
- Calcium metal is less dense than aluminum but much more chemically reactive.
- The Ca²⁺ ion gives brick-red to orange-red colors in flame tests.
- Hard water is often hard because it contains dissolved calcium and magnesium ions.
- Calcium carbonate can exist as calcite, aragonite, or vaterite, with calcite the most stable at surface conditions.
- Calcium signaling in cells works because free Ca²⁺ concentrations are kept very low in the cytosol.
Images
Propriétés
Propriétés physiques
- Rayon atomique (empirique)
- 180 pm Comparer : Rayon atomique (empirique) de tous les éléments →
- Rayon covalent
- 176 pm Comparer : Rayon covalent de tous les éléments →
- Rayon de van der Waals
- 231 pm Comparer : Rayon de van der Waals de tous les éléments →
- Rayon métallique
- 174 pm Comparer : Rayon métallique de tous les éléments →
- Masse volumique
- 1540 kg/m³ Comparer : Masse volumique de tous les éléments →
- Volume molaire
- 0,0299 L/mol
- Phase aux CNTP
- Solide Comparer : Phase aux CNTP de tous les éléments →
- Point de fusion
- 841,85 °C Comparer : Point de fusion de tous les éléments →
- Point d’ébullition
- 1483,85 °C Comparer : Point d’ébullition de tous les éléments →
- Capacité thermique massique
- 0,647 J/(g·K) Comparer : Capacité thermique massique de tous les éléments →
- Capacité thermique molaire
- 25,929 J/(mol·K) Comparer : Capacité thermique molaire de tous les éléments →
- Structure cristalline
- Cubique à faces centrées Comparer : Structure cristalline de tous les éléments →
Propriétés chimiques
- Électronégativité (Pauling)
- 1 Comparer : Électronégativité (Pauling) de tous les éléments →
- Électronégativité (Allen)
- 1,034
- Affinité électronique
- 0,0245 eV
- Énergie d’ionisation (1re)
- 6,113155 eV Comparer : Énergie d’ionisation (1re) de tous les éléments →
- Énergie d’ionisation (2e)
- 11,87176 eV Comparer : Énergie d’ionisation (2e) de tous les éléments →
- Énergie d’ionisation (3e)
- 50,913335 eV Comparer : Énergie d’ionisation (3e) de tous les éléments →
- Énergie d’ionisation (4e)
- 67,273432 eV Comparer : Énergie d’ionisation (4e) de tous les éléments →
- Énergie d’ionisation (5e)
- 84,34029 eV Comparer : Énergie d’ionisation (5e) de tous les éléments →
- États d’oxydation
- +1, +2 Comparer : États d’oxydation de tous les éléments →
- Électrons de valence
- 2 Comparer : Électrons de valence de tous les éléments →
- Configuration électronique
- [Ar] 4s2
Propriétés thermodynamiques
- Enthalpie de fusion
- 0,08851117 eV Comparer : Enthalpie de fusion de tous les éléments →
- Enthalpie de vaporisation
- 1,603358 eV Comparer : Enthalpie de vaporisation de tous les éléments →
- Enthalpie de sublimation
- 1,846919 eV
- Enthalpie d’atomisation
- 1,846919 eV
- Enthalpie d’atomisation
- 1,842773 eV
Propriétés nucléaires
- Protons
- 20 Comparer : Protons de tous les éléments →
- Neutrons
- 24 Comparer : Neutrons de tous les éléments →
- Isotopes connus
- 29 Comparer : Isotopes connus de tous les éléments →
- Isotopes stables
- 4 Comparer : Isotopes stables de tous les éléments →
- Isotope le plus stable
- Ca-44
- Année de découverte
- 1808
Abondance
- Abondance (croûte terrestre)
- 4,15e+4 mg/kg Comparer : Abondance (croûte terrestre) de tous les éléments →
- Abondance (océan)
- 412 mg/L Comparer : Abondance (océan) de tous les éléments →
Structure cristalline
- Paramètre de maille a
- 558 pm
Structure électronique
- Électrons par couche
- 2, 8, 8, 2 Comparer : Électrons par couche de tous les éléments →
Identifiants
- Numéro CAS
- 7440-70-2 Comparer : Numéro CAS de tous les éléments →
- Symbole de terme
- 1S0
- InChI
- InChI=1S/Ca
- Clé InChI
- OYPRJOBELJOOCE-UHFFFAOYSA-N
Configuration électronique Mesuré
Ca: 4s²[Ar] 4s²1s² 2s² 2p⁶ 3s² 3p⁶ 4s²Modèle atomique
Les isotopes diffèrent par leur nombre de neutrons, leur masse et leur stabilité — pas par la configuration électronique de l’atome neutre.
Modèle atomique schématique, non à l’échelle.
Empreinte atomique
Spectre d’émission / d’absorption
Distribution isotopique
| Nombre de masse | Masse atomique (u) | Abondance naturelle | Demi-vie |
|---|---|---|---|
| 42 Stable | 41,95861783 ± 0,00000016 | 0,6470% | Stable |
| 43 Stable | 42,95876644 ± 0,00000024 | 0,1350% | Stable |
| 44 Stable | 43,95548156 ± 0,00000035 | 2,0860% | Stable |
| 46 Stable | 45,953689 ± 0,0000024 | 0,0040% | Stable |
Phase / État
Explication: 816,9 °C en dessous du point de fusion (841,85 °C)
Schématique, non à l’échelle
Points de transition de phase
Énergies de transition
Énergie nécessaire pour faire fondre 1 mol au point de fusion
Énergie nécessaire pour vaporiser 1 mol au point d’ébullition
Énergie nécessaire pour sublimer 1 mol au point de sublimation
Masse volumique
Dans les conditions standard
Dans les conditions standard
Spectres atomiques
Affichage de 10 sur 20. Tri par charge ionique croissante.
Raies répertoriées ?
| Ion | Charge | Nombre total de raies | Probabilités de transition | Désignations des niveaux |
|---|---|---|---|---|
| Ca I | 0 | 206 | 136 | 137 |
| Ca II | +1 | 149 | 99 | 99 |
| Ca III | +2 | 676 | 530 | 676 |
| Ca IV | +3 | 40 | 3 | 3 |
| Ca V | +4 | 53 | 18 | 18 |
| Ca VI | +5 | 20 | 18 | 20 |
| Ca VII | +6 | 18 | 18 | 18 |
| Ca VIII | +7 | 6 | 6 | 6 |
| Ca IX | +8 | 26 | 26 | 26 |
| Ca X | +9 | 25 | 25 | 25 |
Niveaux répertoriés ?
| Ion | Charge | Niveaux |
|---|---|---|
| Ca I | 0 | 787 |
| Ca II | +1 | 72 |
| Ca III | +2 | 182 |
| Ca IV | +3 | 71 |
| Ca V | +4 | 40 |
| Ca VI | +5 | 32 |
| Ca VII | +6 | 27 |
| Ca VIII | +7 | 38 |
| Ca IX | +8 | 72 |
| Ca X | +9 | 52 |
Rayons ioniques
| Charge | Coordinence | Spin | Rayon |
|---|---|---|---|
| +2 | 6 | N/D | 100 pm |
| +2 | 7 | N/D | 106 pm |
| +2 | 8 | N/D | 112.00000000000001 pm |
| +2 | 9 | N/D | 118 pm |
| +2 | 10 | N/D | 123 pm |
| +2 | 12 | N/D | 134 pm |
Composés
Isotopes (4)
| Nombre de masse | Masse atomique (u) | Abondance naturelle | Demi-vie | Mode de désintégration | |
|---|---|---|---|---|---|
| 42 Stable | 41,95861783 ± 0,00000016 | 0,6470% ± 0,0230% | Stable | stable | |
| 43 Stable | 42,95876644 ± 0,00000024 | 0,1350% ± 0,0100% | Stable | stable | |
| 44 Stable | 43,95548156 ± 0,00000035 | 2,0860% ± 0,1100% | Stable | stable | |
| 46 Stable | 45,953689 ± 0,0000024 | 0,0040% ± 0,0030% | Stable | stable |
Raies spectrales
Affichage de 50 sur 247. Seules les raies spectrales dont l’intensité a été mesurée sont affichées par défaut.
| Longueur d’onde (nm) | Intensité | Degré d’ionisation | Type | Transition | Précision | Source | |
|---|---|---|---|---|---|---|---|
| 408.1762 nm | 1000 | Ca III | emission | 3s2.3p5.4s 1P* → 3s2.3p5.4p 3S | Mesurée | NIST | |
| 449.9885 nm | 1000 | Ca III | emission | 3s2.3p5.(2P*<1/2>).4d 2[5/2]* → 3s2.3p5.(2P*<1/2>).4f 2[7/2] | Mesurée | NIST | |
| 420.7216 nm | 800 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4d 2[3/2]* → 3s2.3p5.(2P*<3/2>).4f 2[5/2] | Mesurée | NIST | |
| 430.2803 nm | 800 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4d 2[7/2]* → 3s2.3p5.(2P*<3/2>).4f 2[9/2] | Mesurée | NIST | |
| 439.9584 nm | 800 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4d 2[7/2]* → 3s2.3p5.(2P*<3/2>).4f 2[9/2] | Mesurée | NIST | |
| 423.3736 nm | 700 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4f 2[9/2] → 3s2.3p5.(2P*<3/2>).5g 2[11/2]* | Mesurée | NIST | |
| 440.6286 nm | 700 | Ca III | emission | 3s2.3p5.(2P*<1/2>).4d 2[5/2]* → 3s2.3p5.(2P*<1/2>).4f 2[7/2] | Mesurée | NIST | |
| 451.6586 nm | 700 | Ca III | emission | 3s2.3p5.(2P*<1/2>).4d 2[3/2]* → 3s2.3p5.(2P*<1/2>).4f 2[5/2] | Mesurée | NIST | |
| 457.2125 nm | 700 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4d 2[5/2]* → 3s2.3p5.(2P*<3/2>).4f 2[7/2] | Mesurée | NIST | |
| 424.0742 nm | 600 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4f 2[9/2] → 3s2.3p5.(2P*<3/2>).5g 2[11/2]* | Mesurée | NIST | |
| 443.129 nm | 600 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4d 2[5/2]* → 3s2.3p5.(2P*<3/2>).4f 2[7/2] | Mesurée | NIST | |
| 415.3566 nm | 500 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4d 2[1/2]* → 3s2.3p5.(2P*<3/2>).4f 2[3/2] | Mesurée | NIST | |
| 418.42 nm | 500 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4d 2[1/2]* → 3s2.3p5.(2P*<3/2>).4f 2[3/2] | Mesurée | NIST | |
| 428.4388 nm | 500 | Ca III | emission | 3s2.3p5.(2P*<1/2>).4f 2[7/2] → 3s2.3p5.(2P*<1/2>).5g 2[9/2]* | Mesurée | NIST | |
| 432.9182 nm | 490 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4f 2[7/2] → 3s2.3p5.(2P*<3/2>).5g 2[9/2]* | Mesurée | NIST | |
| 433.3566 nm | 480 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4f 2[7/2] → 3s2.3p5.(2P*<3/2>).5g 2[9/2]* | Mesurée | NIST | |
| 416.4302 nm | 430 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4f 2[3/2] → 3s2.3p5.(2P*<3/2>).5g 2[5/2]* | Mesurée | NIST | |
| 417.565 nm | 410 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4d 2[7/2]* → 3s2.3p5.(2P*<3/2>).4f 2[7/2] | Mesurée | NIST | |
| 427.189 nm | 410 | Ca III | emission | 3s2.3p5.(2P*<1/2>).4f 2[5/2] → 3s2.3p5.(2P*<1/2>).5g 2[7/2]* | Mesurée | NIST | |
| 435.8366 nm | 410 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4d 2[3/2]* → 3s2.3p5.(2P*<1/2>).4f 2[5/2] | Mesurée | NIST | |
| 421.3132 nm | 400 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4d 2[1/2]* → 3s2.3p5.(2P*<3/2>).4f 2[3/2] | Mesurée | NIST | |
| 413.6247 nm | 390 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4f 2[3/2] → 3s2.3p5.(2P*<3/2>).5g 2[5/2]* | Mesurée | NIST | |
| 427.9722 nm | 360 | Ca III | emission | 3s2.3p5.(2P*<1/2>).4f 2[7/2] → 3s2.3p5.(2P*<1/2>).5g 2[9/2]* | Mesurée | NIST | |
| 430.1494 nm | 290 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4d 2[3/2]* → 3s2.3p5.(2P*<3/2>).4f 2[3/2] | Mesurée | NIST | |
| 429.0071 nm | 280 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4f 2[5/2] → 3s2.3p5.(2P*<3/2>).5g 2[7/2]* | Mesurée | NIST | |
| 427.8215 nm | 270 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4d 2[7/2]* → 3s2.3p5.(2P*<3/2>).4f 2[7/2] | Mesurée | NIST | |
| 430.101 nm | 240 | Ca III | emission | 3s2.3p5.(2P*<1/2>).4f 2[5/2] → 3s2.3p5.(2P*<1/2>).5g 2[7/2]* | Mesurée | NIST | |
| 393.3663 nm | 230 | Ca II | emission | 3p6.4s 2S → 3p6.4p 2P* | Mesurée | NIST | |
| 394.9609 nm | 230 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4d 2[5/2]* → 3s2.3p5.(2P*<1/2>).4f 2[7/2] | Mesurée | NIST | |
| 396.8469 nm | 220 | Ca II | emission | 3p6.4s 2S → 3p6.4p 2P* | Mesurée | NIST | |
| 427.3875 nm | 200 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4d 2[7/2]* → 3s2.3p5.(2P*<3/2>).4f 2[7/2] | Mesurée | NIST | |
| 527.1979 nm | 170 | Ca III | emission | 3s2.3p5.(2P*<3/2>).5p 2[5/2] → 3s2.3p5.(2P*<3/2>).5d 2[7/2]* | Mesurée | NIST | |
| 403.8502 nm | 160 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4d 2[1/2]* → 3s2.3p5.(2P*<3/2>).4f 2[5/2] | Mesurée | NIST | |
| 382.376 nm | 150 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4d 2[7/2]* → 3s2.3p5.(2P*<1/2>).4f 2[7/2] | Mesurée | NIST | |
| 448.4948 nm | 150 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4d 2[5/2]* → 3s2.3p5.(2P*<3/2>).4f 2[5/2] | Mesurée | NIST | |
| 470.8836 nm | 150 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4d 2[5/2]* → 3s2.3p5.(2P*<3/2>).4f 2[5/2] | Mesurée | NIST | |
| 471.6287 nm | 130 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4d 2[5/2]* → 3s2.3p5.(2P*<3/2>).4f 2[9/2] | Mesurée | NIST | |
| 606.9998 nm | 110 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4d 2[7/2]* → 3s2.3p5.(2P*<3/2>).5p 2[5/2] | Mesurée | NIST | |
| 524.7373 nm | 100 | Ca III | emission | 3s2.3p5.(2P*<3/2>).5p 2[5/2] → 3s2.3p5.(2P*<3/2>).5d 2[7/2]* | Mesurée | NIST | |
| 393.0884 nm | 90 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4d 2[5/2]* → 3s2.3p5.(2P*<1/2>).4f 2[5/2] | Mesurée | NIST | |
| 485.9165 nm | 90 | Ca III | emission | 3s2.3p5.(2P*<3/2>).5p 2[5/2] → 3s2.3p5.(2P*<3/2>).6s 2[3/2]* | Mesurée | NIST | |
| 500.8939 nm | 90 | Ca III | emission | 3s2.3p5.(2P*<3/2>).5p 2[1/2] → 3s2.3p5.(2P*<3/2>).5d 2[1/2]* | Mesurée | NIST | |
| 532.1287 nm | 90 | Ca III | emission | 3s2.3p5.(2P*<3/2>).5p 2[3/2] → 3s2.3p5.(2P*<3/2>).5d 2[5/2]* | Mesurée | NIST | |
| 434.0345 nm | 80 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4f 2[7/2] → 3s2.3p5.(2P*<3/2>).5g 2[7/2]* | Mesurée | NIST | |
| 441.3732 nm | 80 | Ca III | emission | 3s2.3p5.(2P*<1/2>).4d 2[5/2]* → 3s2.3p5.(2P*<1/2>).4f 2[5/2] | Mesurée | NIST | |
| 450.8788 nm | 80 | Ca III | emission | 3s2.3p5.(2P*<1/2>).4d 2[3/2]* → 3s2.3p5.(2P*<1/2>).4f 2[7/2] | Mesurée | NIST | |
| 463.2855 nm | 80 | Ca III | emission | 3s2.3p5.(2P*<1/2>).5p 2[3/2] → 3s2.3p5.(2P*<1/2>).5d 2[3/2]* | Mesurée | NIST | |
| 501.9971 nm | 80 | Ca II | emission | 3p6.5p 2P* → 3p6.6d 2D | Mesurée | NIST | |
| 505.0089 nm | 80 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4d 2[3/2]* → 3s2.3p5.(2P*<3/2>).4f 2[5/2] | Mesurée | NIST | |
| 557.0601 nm | 80 | Ca III | emission | 3s2.3p5.(2P*<3/2>).4d 2[3/2]* → 3s2.3p5.(2P*<3/2>).5p 2[3/2] | Mesurée | NIST |
Propriétés étendues
Rayons covalents (données étendues)
- Rayon covalent (Pyykkö)
- 171 pm
- Rayon covalent (Pyykkö, liaison double)
- 147 pm
- Rayon covalent (Pyykkö, liaison triple)
- 133 pm
- Rayon covalent (Bragg)
- 170 pm
Rayons de van der Waals
- Truhlar
- 231 pm
- Batsanov
- 240 pm
- Alvarez
- 262 pm
- UFF
- 339,9 pm
- MM3
- 281 pm
Rayons atomiques et métalliques
- Rayon atomique (Rahm)
- 270 pm
- Rayon métallique (C12)
- 197 pm
Échelles de numérotation
- Mendeleev
- 7
- Pettifor
- 16
- Glawe
- 16
Échelles d’électronégativité
- Ghosh
- 0
- Miedema
- 3
- Gunnarsson–Lundqvist
- 3
- Robles–Bartolotti
- 2
Polarisabilité et dispersion
- Polarisabilité dipolaire
- 160,8 a.u.
- Polarisabilité dipolaire (incertitude)
- 4 a.u.
- C₆
- 2163 Ha·Bohr6
- C₆ (Gould–Bučko)
- 2230 Ha·Bohr6
Paramètres de Miedema
- Volume molaire de Miedema
- 26,2 cm3/mol
- Densité électronique de Miedema
- 1
Risque d’approvisionnement et économie
- Concentration de la production
- 65
- Risque relatif d’approvisionnement
- 6
- Stabilité politique (principal producteur)
- 24
Transitions de phase et allotropes
| Point de fusion | 1115,15 K |
| Point d’ébullition | 1757,15 K |
Catégories d’états d’oxydation
Données de référence avancées
Constantes d’écran (6)
| n | Orbitale | σ |
|---|---|---|
| 1 | s | 0,527 |
| 2 | p | 3,9586 |
| 2 | s | 6,2236 |
| 3 | p | 11,3417 |
| 3 | s | 10,3985 |
| 4 | s | 15,602 |
Détail des rayons cristallins (6)
| Charge | CN | Spin | rcrystal (pm) | Origine |
|---|---|---|---|---|
| 2 | VI | 114 | ||
| 2 | VII | 120 | ||
| 2 | VIII | 126 | ||
| 2 | IX | 132 | ||
| 2 | X | 137 | calculated, | |
| 2 | XII | 148 | calculated, |
Modes de désintégration des isotopes (50)
| Isotope | Mode | Intensité |
|---|---|---|
| 33 | p | — |
| 34 | 2p | — |
| 35 | B+ | 100% |
| 35 | B+p | 95,8% |
| 35 | 2p | 4,2% |
| 36 | B+ | 100% |
| 36 | B+p | 51,2% |
| 37 | B+ | 100% |
| 37 | B+p | 76,8% |
| 38 | B+ | 100% |
Facteurs de diffusion des rayons X (504)
| Énergie (eV) | f₁ | f₂ |
|---|---|---|
| 10 | — | 0,0428 |
| 10,1617 | — | 0,04527 |
| 10,3261 | — | 0,04788 |
| 10,4931 | — | 0,05063 |
| 10,6628 | — | 0,05355 |
| 10,8353 | — | 0,05663 |
| 11,0106 | — | 0,05989 |
| 11,1886 | — | 0,06334 |
| 11,3696 | — | 0,06634 |
| 11,5535 | — | 0,06922 |
Données complémentaires
Estimated Crustal Abundance
The estimated element abundance in the earth's crust.
4.15×104 milligrams per kilogram
Références (1)
Estimated Oceanic Abundance
The estimated element abundance in the earth's oceans.
4.12×102 milligrams per liter
Références (1)
Sources
Sources of this element.
Calcium, a metallic element, is fifth in abundance in the earth's crust, of which it forms more than 3%. It is an essential constituent of leaves, bones, teeth, and shells. Never found in nature uncombined, it occurs abundantly as limestone, gypsum, and fluorite. Apatite is the fluorophosphate or chlorophosphate of calcium.
Références (1)
- [6] Calcium https://periodic.lanl.gov/20.shtml
Références
(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 Calcium.
The element property data was retrieved from publications.