Ca Periodic Table

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Calcium was discovered by Sir Humphry Davy (GB) in 1808. The origin of the name comes from the Latin word calx meaning lime. It is a fairly hard, silvery-white metal. Exposed surfaces form oxides and nitrides. Calcium reacts with water and oxygen. It only occurs in compounds. Calcium is obtained from minerals like chalk, limestone and marble. Periodic Table of the Elements for the Grade Eight and High School California Science Test Copyright © 2019 California Department of Education. Periodic table - chart of all chemical elements Each chemical element contains a link to a page that explains its chemical properties, health effects, environmental effects, application data, an image and also information of the history/inventor of each element. Now available: history of the periodic table.

Mg And Ca Periodic Table

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Timothy P. Hanusa
Professor, Department of Chemistry, Vanderbilt University, Nashville, Tennessee.
Alternative Title: Ca

Calcium (Ca), chemical element, one of the alkaline-earth metals of Group 2 (IIa) of the periodic table. It is the most abundant metallic element in the human body and the fifth most abundant element in Earth’s crust.

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Ca Periodic Table Element

Element Properties
atomic number20
atomic weight40.078
melting point842 °C (1,548 °F)
boiling point1,484 °C (2,703 °F)
specific gravity1.55 (20 °C, or 68 °F)
oxidation state+2
electron configuration1s22s22p63s23p64s2

Occurrence, properties, and uses

Calcium does not occur naturally in the free state, but compounds of the element are widely distributed. One calcium compound, lime (calcium oxide, CaO) was extensively used by the ancients. The silvery, rather soft, lightweight metal itself was first isolated (1808) by Sir Humphry Davy after distilling mercury from an amalgam formed by electrolyzing a mixture of lime and mercuric oxide. The name for the element was taken from the Latin word for lime, calx.

Calcium constitutes 3.64 percent of Earth’s crust and 8 percent of the Moon’s crust, and its cosmic abundance is estimated at 4.9 × 104atoms (on a scale where the abundance of silicon is 106 atoms). As calcite (calcium carbonate), it occurs on Earth in limestone, chalk, marble, dolomite, eggshells, pearls, coral, stalactites, stalagmites, and the shells of many marine animals. Calcium carbonate deposits dissolve in water that contains carbon dioxide to form calcium bicarbonate, Ca(HCO3)2. This process frequently results in the formation of caves and may reverse to deposit limestone as stalactites and stalagmites. As calcium hydroxyl phosphate, it is the principal inorganic constituent of teeth and bones and occurs as the mineralapatite. As calcium fluoride, it occurs as fluorite, or fluorspar. And as calcium sulfate, it occurs as anhydrite. Calcium is found in many other minerals, such as aragonite (a type of calcium carbonate) and gypsum (another form of calcium sulfate), and in many feldspars and zeolites. It is also found in a large number of silicates and aluminosilicates, in salt deposits, and in natural waters, including the sea.

Formerly produced by electrolysis of anhydrous calcium chloride, pure calcium metal is now made commercially by heating lime with aluminum. The metal reacts slowly with oxygen, water vapour, and nitrogen of the air to form a yellow coating of the oxide, hydroxide, and nitride. It burns in air or pure oxygen to form the oxide and reacts rapidly with warm water (and more slowly with cold water) to produce hydrogen gas and calcium hydroxide. On heating, calcium reacts with hydrogen, halogens, boron, sulfur, carbon, and phosphorus. Although it compares favourably with sodium as a reducing agent, calcium is more expensive and less reactive than the latter. In many deoxidizing, reducing, and degasifying applications, however, calcium is preferred because of its lower volatility and is used to prepare chromium, thorium, uranium, zirconium, and other metals from their oxides.

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The metal itself is used as an alloying agent for aluminum, copper, lead, magnesium, and other base metals; as a deoxidizer for certain high-temperature alloys; and as a getter in electron tubes. Small percentages of calcium are used in many alloys for special purposes. Alloyed with lead (0.04 percent calcium), for example, it is employed as sheaths for telephone cables and as grids for storage batteries of the stationary type. When added to magnesium-based alloys in amounts from 0.4 to 1 percent, it improves the resistance of degradable orthopedic implants to biological fluids, permitting tissues to heal fully before the implants lose their structural integrity.

Naturally occurring calcium consists of a mixture of six isotopes: calcium-40 (96.94 percent), calcium-44 (2.09 percent), calcium-42 (0.65 percent), and, in smaller proportions, calcium-48, calcium-43, and calcium-46. Calcium-48 undergoes double beta decay with a half-life of roughly 4 × 1019 years, so it is stable for all practical purposes. It is particularly neutron-rich and is used in the synthesis of new heavy nuclei in particle accelerators. The radioactive isotope calcium-41 occurs in trace quantities on Earth through the natural bombardment of calcium-40 by neutrons in cosmic rays.

Calcium is essential to both plant and animallife and is broadly employed as a signal transducer, enzymecofactor, and structural element (e.g., cell membranes, bones, and teeth). A large number of living organisms concentrate calcium in their shells or skeletons, and in higher animals calcium is the most abundant inorganic element. Many important carbonate and phosphate deposits owe their origin to living organisms.

The human body is 2 percent calcium. Major sources of calcium in the human diet are milk, milk products, fish, and green leafy vegetables. The bone diseaserickets occurs when a lack of vitamin D impairs the absorption of calcium from the gastrointestinal tract into the extracellular fluids. The disease especially affects infants and children.

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Element Calcium - Ca

Comprehensive data on the chemical element Calcium is provided on this page; including scores of properties, element names in many languages, most known nuclides of Calcium. Common chemical compounds are also provided for many elements. In addition technical terms are linked to their definitions and the menu contains links to related articles that are a great aid in one's studies.

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Overview of Calcium

  • Atomic Number: 20
  • Group: 2
  • Period: 4
  • Series: Alkali Earth Metals

Calcium's Name in Other Languages

  • Latin: Calcium
  • Czech: Vápník
  • Croatian: Kalcij
  • French: Calcium
  • German: Kalzium - r
  • Italian: Calcio
  • Norwegian: Kalsium
  • Portuguese: Cálcio
  • Russian: Кальций
  • Spanish: Calcio
  • Swedish: Kalcium

Atomic Structure of Calcium

  • Atomic Radius: 2.23Å
  • Atomic Volume: 29.9cm3/mol
  • Covalent Radius: 1.74Å
  • Cross Section (Thermal Neutron Capture)σa/barns: 0.43
  • Crystal Structure: Cubic face centered
  • Electron Configuration:
    1s2 2s2p6 3s2p6 4s2
  • Electrons per Energy Level: 2,8,8,2
    Shell Model
  • Ionic Radius: 0.99Å
  • Filling Orbital: 4s2
  • Number of Electrons (with no charge): 20
  • Number of Neutrons (most common/stable nuclide): 20
  • Number of Protons: 20
  • Oxidation States: 2
  • Valence Electrons: 4s2
    Electron Dot Model

Chemical Properties of Calcium

  • Electrochemical Equivalent: 0.7477g/amp-hr
  • Electron Work Function: 2.87eV
  • Electronegativity: 1 (Pauling); 1.04 (Allrod Rochow)
  • Heat of Fusion: 8.54kJ/mol
  • Incompatibilities:
    water, oxidizers, acids, air, chlorine, chlorine tri-fluoride, fluorine, oxygen, silicon, sulfur
  • Ionization Potential
    • First: 6.113
    • Second: 11.871
    • Third: 50.908
  • Valence Electron Potential (-eV): 29
Ca Periodic Table

Physical Properties of Calcium

  • Atomic Mass Average: 40.078
  • Boiling Point: 1757K 1484°C 2703°F
  • Coefficient of lineal thermal expansion/K-1: 22E-6
  • Conductivity
    Electrical: 0.298 106/cm Ω
    Thermal: 2.01 W/cmK
  • Density: 1.55g/cc @ 300K
  • Description:
    silvery, soft metal, tarnishes to grayish white after exposure to air.
  • Elastic Modulus:
    • Bulk: 17/GPa
    • Rigidity: 7.4/GPa
    • Youngs: 20/GPa
  • Enthalpy of Atomization: 184 kJ/mole @ 25°C
  • Enthalpy of Fusion: 8.54 kJ/mole
  • Enthalpy of Vaporization: 150 kJ/mole
  • Flammablity Class: Flammable solid
  • Freezing Point:see melting point
  • Hardness Scale
    • Brinell: 167 MN m-2
    • Mohs: 1.75
  • Heat of Vaporization: 153.6kJ/mol
  • Melting Point: 1112K 839°C 1542°F
  • Molar Volume: 26.02 cm3/mole
  • Physical State (at 20°C & 1atm): Solid
  • Specific Heat: 0.632J/gK
  • Vapor Pressure = [email protected]°C

Regulatory / Health

  • CAS Number
    • 7440-70-2
  • RTECS: EV8040000
  • NFPA 704
    • Health: 1
    • Fire: 1
    • Reactivity: 2
    • Special Hazard:
  • OSHAPermissible Exposure Limit (PEL)
    • No limits set by OSHA
  • OSHA PEL Vacated 1989
    • No limits set by OSHA
  • NIOSHRecommended Exposure Limit (REL)
    • No limits set by NIOSH
  • Levels In Humans:
    Note: this data represents naturally occuring levels of elements in the typical human, it DOES NOT represent recommended daily allowances.
    • Blood/mg dm-3: 60.5
    • Bone/p.p.m: 170000
    • Liver/p.p.m: 100-360
    • Muscle/p.p.m: 140-700
    • Daily Dietary Intake: 600-1400 mg
    • Total Mass In Avg. 70kg human: 1 kg

Who / Where / When / How

  • Discoverer: Sir Humphrey Davy
  • Discovery Location: London England
  • Discovery Year: 1808
  • Name Origin:
    Latin: calx, calcis (lime).
  • Abundance of Calcium:
    • Earth's Crust/p.p.m.: 41000
    • Seawater/p.p.m.: 390
    • Atmosphere/p.p.m.: N/A
    • Sun (Relative to H=1E12): 2240000
  • Sources of Calcium:
    Obtained from minerals like chalk, limestone & marble. Very abundant. Makes up 3.5% of crust. Occurs only in compounds. World production in 2000 was around 112,000,000 tons (CaO). Calcium is mined almost everywhere.
  • Uses of Calcium:
    Used for dehydrating oils, decarburization and desulfurization of iron and its alloys, getter in vacuum tubes. Also used as an alloying agent for aluminum, copper and lead, a reducing agent for beryllium and used in fertilizer, concrete & plaster of paris. Calcium is an essential component shells, bones, teeth and plant structures.
  • Additional Notes:
    Calcium was prepared as lime by the Romans under the name calyx in the 1st century A.D., but the metal was not discovered until 1808. Berzelius and Pontin prepared calcium amalgam by electrolizing lime in mercury. Davy was then successful in isolating the impure metal. Why did it take so long? Calcium is the fifth most abundant metalic element in the earth's crust, but is never found in the elemental form because it is so reactive. It is found in limestone (CaCO3) gypsum (CaSO4. 2H2O) and fluorite (CaF2). Pure calcium is a shiny soft metal that will react violently with water to produce hydrogen.

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A list of reference sources used to compile the data provided on our periodic table of elements can be found on the main periodic table page.

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