Calcium is a chemical element with symbol Ca and atomic number 20. Calcium is a soft gray Alkaline Earth Metal, fifth-most-abundant element by mass in the Earth's crust. The ion Ca2+ is also the fifth-most-abundant dissolved ion in seawater by both molarity and mass, after sodium, chloride, magnesium, and sulfate.
It belongs to group 2 of the periodic table having trivial name alkaline earth metals*.
Read key information and facts about element Calcium
|Classification||Alkaline Earth Metal|
|Group in Periodic Table||2|
|Group Name||beryllium family|
|Period in Periodic Table||period 4|
|Block in Periodic Table||s -block|
|Electronic Configuration||[Ar] 4s2|
|Electronic Shell Structure (Electrons per shell)||2, 8, 8, 2|
|Melting Point||1115 K|
|Boiling Point||1757 K|
How to Locate Calcium on Periodic Table
Periodic table is arranged by atomic number, number of protons in the nucleus which is same as number of electrons. The atomic number increases from left to right. Periodic table starts at top left ( Atomic number 1) and ends at bottom right (atomic number 118). Therefore you can directly look for atomic number 20 to find Calcium on periodic table.
Another way to read periodic table and locate an element is by using group number (column) and period number (row). To locate Calcium on periodic table look for cross section of group 2 and period 4 in the modern periodic table.
The element Calcium was discovered by H. Davy in year 1808 in United Kingdom. Calcium was first isolated by H. Davy in 1808. Calcium derived its name from the Latin calx, meaning 'lime'.
Davy discovered the metal by electrolysis of quicklime.
Calcium Presence: Abundance in Nature and Around Us
The table below shows the abundance of Calcium in Universe, Sun, Meteorites, Earth's Crust, Oceans and Human Body.
|ppb by weight (1ppb =10^-7 %)||ppb by atoms (1ppb =10^-7 %)|
|Abundance in Universe||70000||2000|
|Abundance in Sun||70000||2000|
|Abundance in Meteorites||11000000||5200000|
|Abundance in Earth's Crust||50000000||26000000|
|Abundance in Oceans||4220||650|
|Abundance in Humans||14000000||2200000|
Crystal Structure of Calcium
The solid state structure of Calcium is Face Centered Cubic.
The Crystal structure can be described in terms of its unit Cell. The unit Cells repeats itself in three dimensional space to form the structure.
Unit Cell Parameters
The unit cell is represented in terms of its lattice parameters, which are the lengths of the cell edges Lattice Constants (a, b and c)
|558.84 pm||558.84 pm||558.84 pm|
and the angles between them Lattice Angles (alpha, beta and gamma).
The positions of the atoms inside the unit cell are described by the set of atomic positions ( xi, yi, zi) measured from a reference lattice point.
The symmetry properties of the crystal are described by the concept of space groups. All possible symmetric arrangements of particles in three-dimensional space are described by the 230 space groups (219 distinct types, or 230 if chiral copies are considered distinct.
|Space Group Name||Fm_ 3m|
|Space Group Number||225|
|Crystal Structure||Face Centered Cubic|
|Number of atoms per unit cell||4|
The number of atoms per unit cell in a simple cubic, face-centered cubic and body-centred cubic are 1,4,2 respectively.
Calcium Atomic and Orbital Properties
Calcium atoms have 20 electrons and the electronic shell structure is [2, 8, 8, 2] with Atomic Term Symbol (Quantum Numbers) 1S0.
|Number of Electrons (with no charge)||20|
|Number of Protons||20|
|Number of Neutrons||20|
|Shell structure (Electrons per energy level)||2, 8, 8, 2|
|Electron Configuration||[Ar] 4s2|
|Main Oxidation States||2|
|Oxidation States||1, 2|
|Atomic Term Symbol (Quantum Numbers)||1S0|
Bohr Atomic Model of Calcium - Electrons per energy level
Ground State Electronic Configuration of Calcium - neutral Calcium atom
Abbreviated electronic configuration of Calcium
The ground state abbreviated electronic configuration of Neutral Calcium atom is [Ar] 4s2. The portion of Calcium configuration that is equivalent to the noble gas of the preceding period, is abbreviated as [Ar]. For atoms with many electrons, this notation can become lengthy and so an abbreviated notation is used. This is important as it is the Valence electrons 4s2, electrons in the outermost shell that determine the chemical properties of the element.
Unabbreviated electronic configuration of neutral Calcium
Complete ground state electronic configuration for the Calcium atom, Unabbreviated electronic configuration
1s2 2s2 2p6 3s2 3p6 4s2
Electrons are filled in atomic orbitals as per the order determined by the Aufbau principle, Pauli Exclusion Principle and Hund’s Rule.
Atomic Structure of Calcium
Calcium atomic radius is 194 pm, while it's covalent radius is 174 pm.
|Atomic Radius Calculated|
194 pm (1.94 Å)
|Atomic Radius Empirical|
180 pm (1.8 Å)
|Atomic Volume||25.857 cm3/mol|
|Covalent Radius||174 pm (1.74 Å)|
|Van der Waals Radius||231 pm|
|Neutron Cross Section||0.43|
|Neutron Mass Absorption||0.00037|
Atomic Spectrum of Calcium
Calcium Chemical Properties: Calcium Ionization Energies and electron affinity
The electron affinity of Calcium is 2.37 kJ/mol.
Ionization Energy of Calcium
Refer to table below for Ionization energies of Calcium
|Ionization energy number||Enthalpy - kJ/mol|
Calcium Physical Properties
Refer to below table for Calcium Physical Properties
|Density||1.55 g/cm3(when liquid at m.p density is $1.378 g/cm3)|
|Molar Volume||25.857 cm3/mol|
|Shear Modulus||7.4 GPa|
|Bulk Modulus||17 GPa|
Hardness of Calcium - Tests to Measure of Hardness of Element
|Mohs Hardness||1.75 MPa|
|Brinell Hardness||167 MPa|
Calcium Electrical Properties
Calcium is Conductor of electricity. Refer to table below for the Electrical properties ofCalcium
|Electrical Conductivity||29000000 S/m|
|Resistivity||3.4e-8 m Ω|
Calcium Heat and Conduction Properties
|Thermal Conductivity||200 W/(m K)|
|Thermal Expansion||0.0000223 /K|
Calcium Magnetic Properties
|Mass Magnetic Susceptibility||1.38e-8 m3/kg|
|Molar Magnetic Susceptibility||5.531e-10 m3/mol|
|Volume Magnetic Susceptibility||0.00002139|
Optical Properties of Calcium
Acoustic Properties of Calcium
|Speed of Sound||3810 m/s|
Calcium Thermal Properties - Enthalpies and thermodynamics
Refer to table below for Thermal properties of Calcium
|Melting Point||1115 K (841.85°C, 1547.3300000000002 °F)|
|Boiling Point||1757 K (1483.85°C, 2702.93 °F)|
Enthalpies of Calcium
|Heat of Fusion||8.54 kJ/mol|
|Heat of Vaporization||155 kJ/mol|
|Heat of Combustion||-990 J/(kg K)|
Calcium Isotopes - Nuclear Properties of Calcium
Calcium has 24 isotopes, with between 34 and 57 nucleons. Calcium has 5 stable naturally occuring isotopes.
Isotopes of Calcium - Naturally occurring stable Isotopes: 40Ca, 42Ca, 43Ca, 44Ca, 46Ca.
|Isotope||Z||N||Isotope Mass||% Abundance||T half||Decay Mode|
Regulatory and Health - Health and Safety Parameters and Guidelines
|DOT Hazard Class||4.2|
|NFPA Fire Rating||1|
|NFPA Hazards||Water Reactive|
|NFPA Health Rating||3|
|NFPA Reactivity Rating||2|
List of unique identifiers to search the element in various chemical registry databases
|CAS Number - Chemical Abstracts Service (CAS)||CAS7440-70-2|
Compare Calcium with other elements
Compare Calcium with all Group 2 elements
Compare Calcium with all Period 4 elements
Compare Calcium with all Alkaline Earth Metal elements
What is the electronic configuration of Calcium?
The electronic configuration of Calcium is 1s2 2s2 2p6 3s2 3p6 4s2.
What is the abbreviated electronic configuration of Calcium?
The abbreviated electronic configuration of Calcium is [Ar] 4s2. To form abbreviated notation of electronic configuration, the completely filled subshells are replaced by the noble gas of the preceding period in square brackets.
What is the symbol of Calcium?
Symbol of Calcium is Ca. Calcium is a chemical element with symbol Ca and atomic number 20.
What is the position of Calcium in the Periodic Table?
Calcium is a chemical element with the symbol Ca and atomic number 20. Calcium is the 20 element on the periodic table. It is located in group 2 and period 4 in the modern periodic table.
What is the atomic number of Calcium?
The atomic number of Calcium is 20.
What is the color of Calcium?
Calcium is of Silver color.
Who discovered Calcium?
The element Calcium was discovered by H. Davy in year 1808 in United Kingdom. Calcium was first isolated by H. Davy in 1808.
How many valence electrons does a Calcium atom have?
Calcium has 2 valence electrons. Calcium has 20 electrons out of which 2 valence electrons are present in the 4s2 outer orbitals of atom.
What is the melting Point of Calcium?
Melting Point of Calcium is 1115 K.
What is the boiling Point of Calcium?
Boiling Point of Calcium is 1757 K.
What is the melting Point of Calcium in Kelvin?
Melting Point of Calcium in Kelvin is 1115 K.
What is the boiling Point of Calcium in Kelvin?
Boiling Point of Calcium in Kelvin is 1757 K.
What is the electronic configuration of Calcium 20?
The electronic configuration of Calcium will be 1s2 2s2 2p6 3s2 3p6 4s2.
How do you write the electron configuration for Calcium?
The electronic configuration of Calcium will be 1s2 2s2 2p6 3s2 3p6 4s2.