Beryllium naturally occurring isotope

Strontium has four naturally occurring isotopes (Table 4.2). It is a member of the alkaline earths (Group 2A) along with beryllium, magnesium, calcium, barium, and radium (Fig. 2.4). Strontium substitutes for calcium and is abundant in minerals such as plagioclase, apatite, and calcium carbonate. 

The only elements with only one naturally occurring isotope are beryllium, sodium, aluminum, and phosphorus. 

Only one naturally occurring isotope of beryllium exists beryllium-9. Isotopes are two or more forms of an element. Isotopes differ from each other according to their mass number. The number written to the right of the element s name is the mass number. The mass number represents the number of protons plus neutrons in the nucleus of an atom of the element. The number of protons determines the element, but the number of neutrons in the atom of any one element can vary. Each variation is an isotope. 

All atoms of a given element have the same number of protons however, they do not necessarily have the same number of neutrons. Since neutrons and protons have nearly the same mass (approximately 1 amu), and since the number of neutrons in the atoms of a given element can vary, all atoms of a given element do not have the same mass (contrary to what John Dalton originally proposed in his atomic theory). For example, all neon atoms in nature contain 10 protons, but they may have 10, 11, or 12 neutrons (T Figure 4.15). All three t) es of neon atoms exist, and each has a slightly different mass. Atoms with the same number of protons but different numbers of neutrons are called isotopes. Some elements, such as beryllium (Be) and aluminum (Al), have only one naturally occurring isotope, while other elements, such as neon (Ne) and chlorine (Cl), have two or more. 

Some elements do exist in only one naturally occurring stable isotope, and therefore, they are termed monoisotopic elements. Among these, fluorine ( ), sodium ( Na), phosphorus ( P) and iodine belong to the more prominent examples in organic mass spectrometry, but there are several more such as beryllium ( Be), aluminum ( Al), scandium (" Sc), manganese ( Mn), cobalt ( Co), arsenic... 

All naturally occurring beryllium compounds are. made up of the Be isotope. Artificially produced isotopes occur during some nuclear reactor operations and include 6Be, 7 Be, sBe, and l0Be. 

There are five known isotopes of beryllium with mass numbers of 6, 7, 8,9, 10, of which Be is stable. The nucleus of this naturally occurring stable isotope consists of nine particles (four protons and five neutrons). The odd neutron is not bound in the nucleus as strongly as the other eight particles, so that beryllium may be used as a neutron source. This neutron emission of beryllium due to irradiation may be applied in quantitative estimates of the beryllium content in minerals and ores [30]. 

All known elements have two or more isotopes. In some cases (beryllium, Be fluorine, F sodium, Na aluminum, Al, etc.) only one isotope occurs naturally, the others being unstable. The maximum number of stable isotopes of any element is 10, possessed by tin. 

The alkaline earth metals show a wider range of chemical properties than the alkali metals. The IIA metals are not as reactive as the lA metals, but they are much too reactive to occur free in nature. They are obtained by electrolysis of their molten chlorides. Calcium and magnesium are abundant in the earth s crust, especially as carbonates and sulfates. Beryllium, strontium, and barium are less abundant. All known radium isotopes are radioactive and are extremely rare. 

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