![]() Davy was trying to isolate calcium and when he heard that Berzelius and Pontin prepared calcium amalgam by electrolyzing lime in mercury, he tried it himself. It was not actually isolated until 1808 in England when Sir Humphry Davy electrolyzed a mixture of lime and mercuric oxide. in the making of cements and mortars to be used in construction.Ĭalcium ( Latin calcis, meaning "lime") was known as early as the first century when the Ancient Romans prepared lime as calcium oxide.as an alloying agent used in the production of aluminium, beryllium, copper, lead, and magnesium alloys.as a deoxidizer, desulfurizer, or decarbonizer for various ferrous and nonferrous alloys.as a reducing agent in the extraction of other metals, such as uranium, zirconium, and thorium.Being an essential macromineral in the human diet, soil conservation practices often consider the sustainable equilibrium of calcium concentrations in the earth. Stalagmites and stalactites contain calcium carbonate. Calcium is found mostly in soil systems as limestone, gypsum and fluorite. The outer shell is the valence shell, with 2 electrons in the lone 4s orbital, the 3d orbitals being empty.Ĭalcium is not naturally found in its elemental state. Its electron configuration is: 2 electrons in the K shell (principal quantum number 1), 8 in the L shell (principal quantum number 2), 8 in the M shell (principal quantum number 3), and 2 in the N shell (principal quantum number 4). ![]() The most abundant isotope, 40Ca, has a nucleus of 20 protons and 20 neutrons. Adults need between 1,000 and 1,300 mg of calcium in their daily diet. In the U.S., between about 50% and 75% of adults do not get sufficient calcium in their diet. It reacts with water, displacing hydrogen and forming calcium hydroxide.Ĭalcium is essential in muscle contraction, oocyte activation, bones and tooth structure, blood clotting, nerve impulse transmission, regulating heartbeat, and fluid balance within cells. It burns with a yellow-red flame and forms a white nitride coating when exposed to air. It may be used as a reducing agent in the extraction of thorium, zirconium and uranium.Ĭalcium is a rather soft, gray, metallic element that can be extracted by electrolysis from calcium fluoride. It is essential for living organisms, particularly in cell physiology, and is the most common metal in many animals. Calcium is a soft grey alkaline earth metal, and is the fifth most abundant element in the Earth's crust. ![]() Therefore, there are various non-equivalent definitions of atomic radius.Calcium ( IPA: /ˈkalsiəm/) is the chemical element in the periodic table that has the symbol Ca and atomic number 20. However, this assumes the atom to exhibit a spherical shape, which is only obeyed for atoms in vacuum or free space. The atomic radius of a chemical element is a measure of the distance out to which the electron cloud extends from the nucleus. It must be noted, atoms lack a well-defined outer boundary. The atomic radius of Calcium atom is 176pm (covalent radius). ![]() Note that, each element may contain more isotopes, therefore this resulting atomic mass is calculated from naturally-occuring isotopes and their abundance. The atomic mass is carried by the atomic nucleus, which occupies only about 10 -12 of the total volume of the atom or less, but it contains all the positive charge and at least 99.95% of the total mass of the atom. The atomic mass or relative isotopic mass refers to the mass of a single particle, and therefore is tied to a certain specific isotope of an element. Mass numbers of typical isotopes of Calcium are 40 42 43 44 46. Isotopes are nuclides that have the same atomic number and are therefore the same element, but differ in the number of neutrons. The difference between the neutron number and the atomic number is known as the neutron excess: D = N – Z = A – 2Z.įor stable elements, there is usually a variety of stable isotopes. Neutron number plus atomic number equals atomic mass number: N+Z=A. The total number of neutrons in the nucleus of an atom is called the neutron number of the atom and is given the symbol N. The total electrical charge of the nucleus is therefore +Ze, where e (elementary charge) equals to 1,602 x 10 -19 coulombs. Total number of protons in the nucleus is called the atomic number of the atom and is given the symbol Z. Atomic Number – Protons, Electrons and Neutrons in CalciumĬalcium is a chemical element with atomic number 20 which means there are 20 protons in its nucleus. ![]()
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