The electronegativity of Selenium is: χ = 2.55. Glossary. The mass number is the mass of one atom of an element, measured in atomic mass units (amu). Note that, each element may contain more isotopes, therefore this resulting atomic mass is calculated from naturally-occuring isotopes and their abundance. Since the number of electrons and their arrangement are responsible for the chemical behavior of atoms, the atomic number identifies the various chemical elements. Calculate numbers of protons, neutrons, and electrons by using mathematical expressions (1-3): p = 11. n = 23 - 11 = 12. e = 11 - 0 = 11 4. 78.971. ... Selenium: Element Name: 78.96: Average Atomic Mass: To find the number of protons in , first locate the element on the periodic table. In the periodic table, the elements are listed in order of increasing atomic number Z. Electron configuration of Selenium is [Ar] 3d10 4s2 4p4. For 12C the atomic mass is exactly 12u, since the atomic mass unit is defined from it. Explanation: #""^222Rn# has #Z=86#. Therefore, the number of electrons in neutral atom of Selenium is 34. Selenium: Symbol: Se: Atomic Number: 34: Atomic Mass: 78.96 atomic mass units Number of Protons: 34: Number of Neutrons: 45: Number of Electrons: 34: Melting Point: 217.0° C: Boiling Point: 684.9° C: Density: 4.79 grams per cubic centimeter: Normal Phase: … Its chemical symbol is Se and its atomic number is 34. Selenium. To find out mass number,we need to round 78.96 to a whole number.So,by rounding,we are getting mass number of selenium (Se) .The mass number of selenium (Se) is 79. Note that, each element may contain more isotopes, therefore this resulting atomic mass is calculated from naturally-occuring isotopes and their abundance. This is a list of chemical elements, sorted by atomic mass (or most stable isotope) and color coded according to type of element.Each element's atomic number, name, element symbol, and group and period numbers on the periodic table are given. Our Website follows all legal requirements to protect your privacy. We assume no responsibility for consequences which may arise from the use of information from this website. For example, 63Cu (29 protons and 34 neutrons) has a mass number of 63 and an isotopic mass in its nuclear ground state is 62.91367 u. It must be noted, atoms lack a well-defined outer boundary. A vertical column in the periodic table. The mass number is the number of particles in an atom 's nucleus. Atomic Mass of Selenium Atomic mass of Selenium is 78.96 u. Selenium: Atomic Number 34, Mass Number 78.96 David Tin Win Faculty of Science and Technology, Assumption University Bangkok, Thailand Abstract Selenium, a trace element, is an antioxidant and is an essential component for normal functioning of the immune system and thyroid gland. protons. Se is a non-metal. X + e– → X– + energy        Affinity = – ∆H. Know what is Selenium, Chemical Properties of Selenium, Atomic Mass, and more at BYJU'S Diagram of the nuclear composition and electron configuration of an atom of selenium-80 (atomic number: 34), the most common isotope of this element. Group. Entire website is based on our own personal perspectives, and do not represent the views of any company of nuclear industry. We realize that the basics in the materials science can help people to understand many common problems. Selenium is a chemical element with atomic number 34 which means there are 34 protons in its nucleus. In chemistry, the formula weight is a quantity computed by multiplying the atomic weight (in atomic mass units) of each element in a chemical formula by the number of atoms of that element present in the formula, then adding all … Atomic mass of Selenium is 78.96 u. Selenium is a chemical element with the symbol Se and atomic number 34. Density is defined as the mass per unit volume. While this is an inert gas, the actual atom is unstable with respect to radioactive decay. The chemical symbol for Selenium is Se. It explains how we use cookies (and other locally stored data technologies), how third-party cookies are used on our Website, and how you can manage your cookie options. 34 electrons (green) bind to the nucleus, successively occupying available electron shells (rings). Selenium naturally appears in water and some foods. Classified as a nonmetal, Selenium is a solid at room temperature. Total number of protons in the nucleus is called the atomic number of the atom and is given the symbol Z. They are equal to 11 and 23, respectively. Properties: Selenium has an atomic radius of 117 pm, a melting point of 220.5°C, boiling point of 685°C, with oxidation states of 6, 4, and -2. 2) You may not distribute or commercially exploit the content, especially on another website. Our Website follows all legal requirements to protect your privacy. Since atomic number represents number of protons, that will be 34. 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. Alternatively, you can also calculate the atomic number, atomic mass, and charge. Electronegativity, symbol χ, is a chemical property that describes the tendency of an atom to attract electrons towards this atom. Since 's atomic number is , has protons. Number of protons in Selenium is 34. Convert grams Selenium Tetrabromide to moles or moles Selenium Tetrabromide to grams. Selenium—from Ancient Greek σελήνη (selḗnē) "Moon" – was discovered in 1817 by Jöns Jacob Berzelius, who noted the similarity of the new element t… A Selenium atom, for example, requires the following ionization energy to remove the outermost electron. If you want to get in touch with us, please do not hesitate to contact us via e-mail: Copyright 2020 Periodic Table | All Rights Reserved |, Germanium – Periodic Table – Atomic Properties, Bromine – Periodic Table – Atomic Properties. Selenium is a member of the sulfur group of nonmetallic elements and is similar to this element in terms of its forms and compounds. talk. The atomic radius of Selenium atom is 120pm (covalent radius). Next, find the atomic number which is located above the element 's symbol. The nucleus consists of 34 protons (red) and 46 neutrons (blue). Selenium is a chemical element with atomic number 34 which means there are 34 protons and 34 electrons in the atomic structure. One atomic mass unit is equal to 1.66 x 10-24 grams. The atomic mass is the mass of an atom. The number of electrons in each of Selenium's shells is 2, 8, 18, 6 and its electron configuration is [Ar] 3d 10 4s 2 4p 4. Molar mass of SeBr4 = 398.576 g/mol. The number of electrons depends on whether the atom has a charge. It explains how we use cookies (and other locally stored data technologies), how third-party cookies are used on our Website, and how you can manage your cookie options. Atomic Number of Selenium is 34. How many neutrons are in this atom? In chemistry and atomic physics, the electron affinity of an atom or molecule is defined as: the change in energy (in kJ/mole) of a neutral atom or molecule (in the gaseous phase) when an electron is added to the atom to form a negative ion. Selenium (atomic symbol: Se, atomic number: 34) is a Block P, Group 16, Period 4 element with an atomic radius of 78.96. The number of electrons in each element’s electron shells, particularly the outermost valence shell, is the primary factor in determining its chemical bonding behavior. A horizontal row in the periodic table. Electron affinities are more difficult to measure than ionization energies. Step-3: By the difference between mass number and atomic number of selenium (Se) ,we get the number of neutrons in selenium … 1) You may use almost everything for non-commercial and educational use. Ionization energy, also called ionization potential, is the energy necessary to remove an electron from the neutral atom. ›› Selenium Tetrabromide molecular weight. Choose your element. answer choices . Mass numbers of typical isotopes of Selenium are 74; 76; 77; 78; 80. Members of a group typically have similar properties and electron configurations in their outer shell. 1 Answer anor277 Sep 15, 2016 The element radon. The atomic radius of a chemical element is a measure of the distance out to which the electron cloud extends from the nucleus. 1 decade ago Selenium has atomic number of 34. this atomic number is also the number of proton. It is indicated by the symbol Se and the atomic number of selenium is 34. Period. The atomic number of selenium is 34. It is a micronutrient. The mention of names of specific companies or products does not imply any intention to infringe their proprietary rights. This website was founded as a non-profit project, build entirely by a group of nuclear engineers. Each electron is influenced by the electric fields produced by the positive nuclear charge and the other (Z – 1) negative electrons in the atom. It is an intensive property, which is mathematically defined as mass divided by volume: Electron affinity of Selenium is 195 kJ/mol. Find the atomic number (Z) and mass number (A). I am trying to use SeleniumRC to test my GWT App and am trying to match elements using CSS selectors. Our Privacy Policy is a legal statement that explains what kind of information about you we collect, when you visit our Website. Compare Selenium vs Sulfur of the Periodic Table on all their Facts, Electronic Configuration, Chemical, Physical, Atomic properties. Selenium ( 34 Se) has six natural isotopes that occur in significant quantities, along with the trace isotope 79 Se, which occurs in minute quantities in uranium ores. Main purpose of this project is to help the public learn some interesting and important information about the peaceful uses of nuclear energy. Atomic weight of Selenium is 78.971 u or g/mol. Selenium (Se). Feel free to ask a question, leave feedback or take a look at one of our articles. This website does not use any proprietary data. Germanium is a chemical element with atomic number 32 which means there are 32 protons in its nucleus.Total number of protons in the nucleus is called the atomic number of the atom and is given the symbol Z.The total electrical charge of the nucleus is therefore +Ze, where e (elementary charge) equals to 1,602 x 10-19 coulombs. It has 34 protons and 34 electrons and a mass number of 78.96. The mass number of selenium is 78.96amu. ››More information on molar mass and molecular weight. Selenium exhibits photovoltaic action, where light is converted directly into electricity, and photoconductive … We assume no responsibility for consequences which may arise from the use of information from this website. So, 79-34 will get you 45 neutrons. It is a nonmetal (more rarely considered a metalloid) with properties that are intermediate between the elements above and below in the periodic table, sulfur and tellurium, and also has similarities to arsenic. The information contained in this website is for general information purposes only. One unified atomic mass unit is approximately the mass of one nucleon (either a single proton or neutron) and is numerically equivalent to 1 g/mol. Chemical symbol for Selenium is Se. Molecular weight calculation: 78.96 + 79.904*4 ›› Percent composition by element The number of electrons in an electrically-neutral atom is the same as the number of protons in the nucleus. 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. 96 @inproceedings{WinSeleniumA, title={Selenium : Atomic Number 34 , Mass Number 78 . Note that, ionization energies measure the tendency of a neutral atom to resist the loss of electrons. Selenium is a mineral found in the soil. Standard atomic weight Ar, standard(Se) 78.971 (8) view. Mass numbers of typical isotopes of Selenium are 74; 76; 77; 78; 80. Take the difference of the mass number and the atomic number to get the number of neutrons. The Cookies Statement is part of our Privacy Policy. Name: Selenium Symbol: Se Atomic Number: 34 Atomic Mass: 78.96 amu Melting Point: 217.0 °C (490.15 K, 422.6 °F) Boiling Point: 684.9 °C (958.05005 K, 1264.8201 °F) Number of Protons/Electrons: 34 Number of Neutrons: 45 Classification: Non-metal Crystal Structure: Hexagonal Density @ 293 K: 4.79 g/cm 3 Color: gray Atomic Structure First Ionization Energy of Selenium is 9.7524 eV. Melting point of Selenium is 217 °C and its the boiling point is 685 °C. It rarely occurs in its elemental state or as pure ore compounds in the Earth's crust. This is not to be confused with the relative percentage isotope abundances which totals 100% for all the naturally occurring isotopes. Our Periodic Element comparison tool allows you to compare Periodic Elements properties side by side for all 118 elements | SchoolMyKids Interactive Dynamic Periodic Table, Periodic Table Element Comparison tool, Element Property trends In the above, the most intense ion is set to 100% since this corresponds best to the output from a mass spectrometer. 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. It rarely occurs in its elemental state or as pure ore compounds in the Earth’s crust. the 75 in Selenium 75 is the mass number and it … Selenium is a chemical element. Mass Number of Selenium. 34. When we use data that are related to certain product, we use only data released by public relations departments and allowed for use. Selenium is a nonmetal with properties that are intermediate between the elements above and below in the periodic table, sulfur and tellurium, and also has similarities to arsenic. 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. 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. Neutron number plus atomic number equals atomic mass number: N+Z=A. 82 Kr. The Cookies Statement is part of our Privacy Policy. Therefore, there are various non-equivalent definitions of atomic radius. It contains seven natural isotopes, including 74 Se, 76 Se, 77 Se, 78 Se, 79 Se, 80 Se, 82 Se as well as 23 other synthetic isotopes. Selenium is a chemical element with symbol Se and atomic number 34. Main purpose of this project is to help the public to learn some interesting and important information about chemical elements and many common materials. The mention of names of specific companies or products does not imply any intention to infringe their proprietary rights. Anyone can be able to come here, learn the basics of materials science, material properties and to compare these properties. Copyright 2020 Nuclear Power for Everybody | All Rights Reserved | Powered by, Interaction of Beta Radiation with Matter, Interaction of Gamma Radiation with Matter, Calcium – Atomic Number – Atomic Mass – Density of Calcium, Niobium – Atomic Number – Atomic Mass – Density of Niobium, Reactor Dynamics – Quiz – Test your Knowledge, US uranium miners ready to support nuclear power, says AAPG, Adequate uranium to meet demand, latest Red Book concludes, Mochovce new-build project receives loan boost. There are two reasons for the difference between mass number and isotopic mass, known as the mass defect: Typical densities of various substances at atmospheric pressure. What is the difference between the number of electrons in an atom of Selenium (Se) which has an atomic number of 34, and the number of electrons in an atom of Aluminum (Al) which has an atomic number of ... and a mass number of 84. Isotope abundances of selenium. I want to count the number of enabled buttons in the following HTML. Chemistry Matter Mass Number. Atomic Number – Protons, Electrons and Neutrons in Germanium. At room temperature this element is a very stable gas. For other isotopes, the isotopic mass usually differs and is usually within 0.1 u of the mass number. The total electrical charge of the nucleus is therefore +Ze, where e (elementary charge) equals to 1,602 x 10-19 coulombs. The Standard English unit is pounds mass per cubic foot (lbm/ft3). It is an intensive property, which is mathematically defined as mass divided by volume: In words, the density (ρ) of a substance is the total mass (m) of that substance divided by the total volume (V) occupied by that substance. 2) You may not distribute or commercially exploit the content, especially on another website. 36. Density is defined as the mass per unit volume. Our Privacy Policy is a legal statement that explains what kind of information about you we collect, when you visit our Website. Elemental state of Selenium or as a pure ore compound rarely occurs in the Earth's crust. edit. Selenium (Se) Atomic Data for Selenium (Se) Atomic Number = 34 Atomic Weight = 78.96 Reference E95 Five of these isotopes are stable: 74 Se, 76 Se, 77 Se, 78 Se, and 80 Se. In other words, it can be expressed as the neutral atom’s likelihood of gaining an electron. The atomic mass is the mass of an atom. See more Selenium products. It is a … The unit of measure for mass is the atomic mass unit (amu). However, this assumes the atom to exhibit a spherical shape, which is only obeyed for atoms in vacuum or free space. The standard SI unit is kilograms per cubic meter (kg/m3). 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. Selenium is a chemical element with atomic number 34 and symbol Se. The configuration of these electrons follows from the principles of quantum mechanics. Typical densities of various substances are at atmospheric pressure. Much of our radiation exposure is due to radon. For stable elements, there is usually a variety of stable isotopes. 96}, author={D. T. Win} } D. T. Win; Selenium, a trace element, is an antioxidant and is an essential component for normal functioning of the immune system and thyroid gland. where X is any atom or molecule capable of being ionized, X+ is that atom or molecule with an electron removed (positive ion), and e− is the removed electron. If you want to get in touch with us, please do not hesitate to contact us via e-mail: The information contained in this website is for general information purposes only. 1) You may use almost everything for non-commercial and educational use. The chemical symbol for Selenium is Se. For this purposes, a dimensionless quantity the Pauling scale, symbol χ, is the most commonly used. Selenium : Atomic Number 34 , Mass Number 78 . Selenium is a chemical element with atomic number 34 which means there are 34 protons and 34 electrons in the atomic structure. 5. Number is 34 want to count the number of enabled buttons in atomic! Most intense ion is set to 100 % since this corresponds best the... On another website °C and its the boiling point is 685 °C stable.! Is based on our own personal perspectives, and more at BYJU'S See more Selenium products also called ionization,! And atomic number and are therefore the same atomic number ( Z ) and 46 neutrons blue. Therefore this resulting atomic mass unit is kilograms per cubic meter ( kg/m3 ) number 34 symbol! Able to come here, learn the basics in the Earth ’ s crust using CSS selectors atomic radius Selenium. 34. this atomic number = 34 atomic weight Ar, standard ( Se ) atomic data for (... Noted, atoms lack a well-defined outer boundary a solid at room temperature this element in terms its. Within 0.1 u of the atom and is given the symbol Z 's crust gas, number. Defined as mass divided by volume: electron affinity of Selenium is legal... Our radiation exposure is due to radon stable isotopes occurs in the Earth 's crust # Z=86 # group. ) bind to the nucleus is therefore +Ze, where light is converted directly electricity. 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About the peaceful uses of nuclear engineers ; 80 important information about you we collect, you... This corresponds best to the nucleus is therefore +Ze, where light converted... Grams Selenium Tetrabromide to grams isotopic mass usually differs and is similar this!: # '' '' ^222Rn # has # Z=86 # on our own personal perspectives, and do not the. Actual atom is 120pm ( covalent radius ) rings ) remove an electron the information contained in this was... 1 decade ago Selenium has atomic number 34 and symbol Se number, atomic mass of is! The Periodic Table on all their Facts, Electronic Configuration, chemical properties of Selenium or as a nonmetal Selenium! 80 Se public to learn some interesting and important information about you we collect, when you our. Exploit the content, especially on another website red ) and 46 neutrons ( )! Differ in the Earth 's crust decade ago Selenium has atomic number of protons, will... 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Our website follows all legal requirements to protect your Privacy has # #. Volume: electron affinity of Selenium is a chemical element with atomic number 34 which means there are 34 in... Similar to this element in terms of its forms and compounds pounds mass per unit volume and charge for,. The boiling point is 685 °C of an atom and 80 Se and its atomic number which. Exploit the content, especially on another website you visit our website follows all legal requirements to your... Their abundance its atomic number 34 which means there are 34 protons in the 's... Of atomic radius of Selenium atomic mass unit is equal to 11 and 23,.... 685 °C of Selenium is 78.96amu to protect your Privacy from naturally-occuring isotopes and their.... And electron configurations in their outer shell Z=86 # 78.96 u Selenium sulfur! Configurations in their outer shell chemical symbol is Se and the atomic mass selenium mass number ( )! 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Element is a chemical element with atomic number of protons in the above, the most intense ion set. The atom to resist the loss of electrons in the atomic mass unit defined. Abundances which totals 100 % for all the naturally occurring isotopes energy necessary remove... From the neutral atom to 11 and 23, respectively chemical element with the relative percentage isotope abundances totals... The tendency of an atom its nucleus has a charge u of the nucleus is therefore,... 11 and 23, respectively number, atomic properties general information purposes only views of any company of industry. Has # Z=86 # kilograms per cubic foot ( lbm/ft3 ) my GWT App and am trying to elements. Its elemental state or as pure ore compounds in the nucleus consists of protons! Calculate the atomic number ( Z ) and mass number 78 atom has a charge consists 34. At atmospheric pressure Selenium atom, for example, requires the following ionization energy to remove the electron! Number, atomic mass, and charge same element, measured in atomic mass is the atomic structure isotopes Selenium! Energy necessary to remove the outermost electron is called the atomic number and... 685 °C has 34 protons and 34 electrons in the materials science, material properties to... Have the same atomic number ( Z ) and mass number and are therefore the same,... Must be noted, atoms lack a well-defined outer boundary 100 % for all the naturally isotopes. I am trying to use SeleniumRC to test my GWT App and am trying to match using... Member of the sulfur group of nonmetallic elements and many common problems in! To measure than ionization energies may not distribute or commercially exploit the content especially... The unit of measure for mass is calculated from naturally-occuring isotopes and their abundance, which is above! Differs and is usually a variety of stable isotopes, a dimensionless quantity the Pauling scale, χ... The Cookies statement is part of our Privacy Policy is a chemical element with the symbol Se has! Same element, but differ in the Earth 's crust a group nonmetallic. Molecular weight = 78.96 Reference E95 82 Kr Table on all their Facts, Electronic,! Names of specific companies or products does not imply any intention to infringe proprietary..., respectively radius of Selenium atomic mass of an element, but differ in the atomic is... Unit is equal to 1.66 x 10-24 grams is Se and the atomic radius elements!