Since the number of electrons and their arrangement are responsible for the chemical behavior of atoms, the atomic number identifies the various chemical elements. Number of protons in Selenium is 34. The difference between the neutron number and the atomic number is known as the neutron excess: D = N – Z = A – 2Z. 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. 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. 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. 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. Selenium is a chemical element. 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 … For 12C the atomic mass is exactly 12u, since the atomic mass unit is defined from it. It is a micronutrient. The mention of names of specific companies or products does not imply any intention to infringe their proprietary rights. 96 @inproceedings{WinSeleniumA, title={Selenium : Atomic Number 34 , Mass Number 78 . Our Website follows all legal requirements to protect your privacy. 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. Se is a non-metal. The unit of measure for mass is the atomic mass unit (amu). Mass numbers of typical isotopes of Selenium are 74; 76; 77; 78; 80. They are equal to 11 and 23, respectively. 82 Kr. ... Selenium: Element Name: 78.96: Average Atomic Mass: To find the number of protons in , first locate the element on the periodic table. Density is defined as the mass per unit volume. Selenium is a chemical element with the symbol Se and atomic number 34. 34. 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. Selenium—from Ancient Greek σελήνη (selḗnē) "Moon" – was discovered in 1817 by Jöns Jacob Berzelius, who noted the similarity of the new element t… 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. Each electron is influenced by the electric fields produced by the positive nuclear charge and the other (Z – 1) negative electrons in the atom. Main purpose of this project is to help the public to learn some interesting and important information about chemical elements and many common materials. I want to count the number of enabled buttons in the following HTML. 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. Selenium (Se) Atomic Data for Selenium (Se) Atomic Number = 34 Atomic Weight = 78.96 Reference E95 talk. Five of these isotopes are stable: 74 Se, 76 Se, 77 Se, 78 Se, and 80 Se. Atomic Number – Protons, Electrons and Neutrons in Germanium. See more Selenium products. Atomic Number of Selenium is 34. Our Website follows all legal requirements to protect your privacy. X + e– → X– + energy        Affinity = – ∆H. The mention of names of specific companies or products does not imply any intention to infringe their proprietary rights. 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. The nucleus consists of 34 protons (red) and 46 neutrons (blue). Find the atomic number (Z) and mass number (A). Selenium exhibits photovoltaic action, where light is converted directly into electricity, and photoconductive … Calculate numbers of protons, neutrons, and electrons by using mathematical expressions (1-3): p = 11. n = 23 - 11 = 12. e = 11 - 0 = 11 4. ›› Selenium Tetrabromide molecular weight. 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. Selenium is a chemical element with atomic number 34 which means there are 34 protons in its nucleus. The atomic mass is the mass of an atom. Selenium is a chemical element with atomic number 34 which means there are 34 protons and 34 electrons in the atomic structure. Alternatively, you can also calculate the atomic number, atomic mass, and charge. When we use data that are related to certain product, we use only data released by public relations departments and allowed for use. 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. 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. The standard SI unit is kilograms per cubic meter (kg/m3). ››More information on molar mass and molecular weight. 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. 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. While this is an inert gas, the actual atom is unstable with respect to radioactive decay. 1) You may use almost everything for non-commercial and educational use. Selenium : Atomic Number 34 , Mass Number 78 . Compare Selenium vs Sulfur of the Periodic Table on all their Facts, Electronic Configuration, Chemical, Physical, Atomic properties. Atomic weight of Selenium is 78.971 u or g/mol. The Standard English unit is pounds mass per cubic foot (lbm/ft3). Much of our radiation exposure is due to radon. In the above, the most intense ion is set to 100% since this corresponds best to the output from a mass spectrometer. 2) You may not distribute or commercially exploit the content, especially on another website. Selenium is a mineral found in the soil. The chemical symbol for Selenium is Se. 1 decade ago Selenium has atomic number of 34. this atomic number is also the number of proton. For this purposes, a dimensionless quantity the Pauling scale, symbol χ, is the most commonly used. Therefore, the number of electrons in neutral atom of Selenium is 34. 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. Electron affinities are more difficult to measure than ionization energies. 1 Answer anor277 Sep 15, 2016 The element radon. Entire website is based on our own personal perspectives, and do not represent the views of any company of nuclear industry. Selenium (atomic symbol: Se, atomic number: 34) is a Block P, Group 16, Period 4 element with an atomic radius of 78.96. This website was founded as a non-profit project, build entirely by a group of nuclear engineers. 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. Molecular weight calculation: 78.96 + 79.904*4 ›› Percent composition by element answer choices . Typical densities of various substances are at atmospheric pressure. A Selenium atom, for example, requires the following ionization energy to remove the outermost electron. Melting point of Selenium is 217 °C and its the boiling point is 685 °C. We realize that the basics in the materials science can help people to understand many common problems. Selenium. Note that, each element may contain more isotopes, therefore this resulting atomic mass is calculated from naturally-occuring isotopes and their abundance. It has 34 protons and 34 electrons and a mass number of 78.96. Its chemical symbol is Se and its atomic number is 34. Density is defined as the mass per unit volume. This website does not use any proprietary data. Feel free to ask a question, leave feedback or take a look at one of our articles. The total electrical charge of the nucleus is therefore +Ze, where e (elementary charge) equals to 1,602 x 10-19 coulombs. In the periodic table, the elements are listed in order of increasing atomic number Z. Electron configuration of Selenium is [Ar] 3d10 4s2 4p4. Members of a group typically have similar properties and electron configurations in their outer shell. 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 Atomic Mass of Selenium Atomic mass of Selenium is 78.96 u. Classified as a nonmetal, Selenium is a solid at room temperature. How many neutrons are in this atom? Electronegativity, symbol χ, is a chemical property that describes the tendency of an atom to attract electrons towards this atom. Our Privacy Policy is a legal statement that explains what kind of information about you we collect, when you visit our Website. Diagram of the nuclear composition and electron configuration of an atom of selenium-80 (atomic number: 34), the most common isotope of this element. 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: … Chemical symbol for Selenium is Se. 2) You may not distribute or commercially exploit the content, especially on another website. Choose your element. 1) You may use almost everything for non-commercial and educational use. A horizontal row in the periodic table. Explanation: #""^222Rn# has #Z=86#. Anyone can be able to come here, learn the basics of materials science, material properties and to compare these properties. Mass Number of Selenium. edit. The mass number is the number of particles in an atom 's nucleus. It rarely occurs in its elemental state or as pure ore compounds in the Earth's crust. 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. It rarely occurs in its elemental state or as pure ore compounds in the Earth’s crust. Convert grams Selenium Tetrabromide to moles or moles Selenium Tetrabromide to grams. Chemistry Matter Mass Number. Note that, ionization energies measure the tendency of a neutral atom to resist the loss of electrons. 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. We assume no responsibility for consequences which may arise from the use of information from this website. Selenium is a chemical element with symbol Se and atomic number 34. 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. Therefore, there are various non-equivalent definitions of atomic radius. 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. Period. 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. The atomic radius of Selenium atom is 120pm (covalent radius). Step-3: By the difference between mass number and atomic number of selenium (Se) ,we get the number of neutrons in selenium … Next, find the atomic number which is located above the element 's symbol. One atomic mass unit is equal to 1.66 x 10-24 grams. 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 It is indicated by the symbol Se and the atomic number of selenium is 34. Isotopes are nuclides that have the same atomic number and are therefore the same element, but differ in the number of neutrons. Elemental state of Selenium or as a pure ore compound rarely occurs in the Earth's crust. The number of electrons in an electrically-neutral atom is the same as the number of protons in the nucleus. 5. The configuration of these electrons follows from the principles of quantum mechanics. In other words, it can be expressed as the neutral atom’s likelihood of gaining an electron. I am trying to use SeleniumRC to test my GWT App and am trying to match elements using CSS selectors. Mass numbers of typical isotopes of Selenium are 74; 76; 77; 78; 80. The information contained in this website is for general information purposes only. Molar mass of SeBr4 = 398.576 g/mol. Take the difference of the mass number and the atomic number to get the number of neutrons. Selenium naturally appears in water and some foods. 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. Our Privacy Policy is a legal statement that explains what kind of information about you we collect, when you visit our Website. 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. The chemical symbol for Selenium is Se. The atomic mass is the mass of an atom. Group. Glossary. 36. Selenium is a member of the sulfur group of nonmetallic elements and is similar to this element in terms of its forms and compounds. The atomic number of selenium is 34. At room temperature this element is a very stable gas. It is an intensive property, which is mathematically defined as mass divided by volume: Electron affinity of Selenium is 195 kJ/mol. Ionization energy, also called ionization potential, is the energy necessary to remove an electron from the neutral atom. It must be noted, atoms lack a well-defined outer boundary. However, this assumes the atom to exhibit a spherical shape, which is only obeyed for atoms in vacuum or free space. So, 79-34 will get you 45 neutrons. 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. The number of electrons depends on whether the atom has a charge. Know what is Selenium, Chemical Properties of Selenium, Atomic Mass, and more at BYJU'S 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. 34 electrons (green) bind to the nucleus, successively occupying available electron shells (rings). For other isotopes, the isotopic mass usually differs and is usually within 0.1 u of the mass number. the 75 in Selenium 75 is the mass number and it … The atomic radius of a chemical element is a measure of the distance out to which the electron cloud extends from the nucleus. 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. For stable elements, there is usually a variety of stable isotopes. This is not to be confused with the relative percentage isotope abundances which totals 100% for all the naturally occurring isotopes. The Cookies Statement is part of our Privacy Policy. 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. The electronegativity of Selenium is: χ = 2.55. Since atomic number represents number of protons, that will be 34. Main purpose of this project is to help the public learn some interesting and important information about the peaceful uses of nuclear energy. Selenium is a chemical element with atomic number 34 and symbol Se. Total number of protons in the nucleus is called the atomic number of the atom and is given the symbol Z. Since 's atomic number is , has protons. Selenium (Se). Selenium is a chemical element with atomic number 34 which means there are 34 protons and 34 electrons in the atomic structure. It is a … 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. protons. Standard atomic weight Ar, standard(Se) 78.971 (8) view. Isotope abundances of selenium. 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. A vertical column in the periodic table. 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. 78.971. First Ionization Energy of Selenium is 9.7524 eV. Atomic mass of Selenium is 78.96 u. We assume no responsibility for consequences which may arise from the use of information from this website. The Cookies Statement is part of our Privacy Policy. The mass number of selenium is 78.96amu. These isotopes are nuclides that have the same element, measured in mass... { Selenium: atomic number of 34. this atomic number 34, number. Or take a look at one of our radiation exposure is due to radon % since this corresponds best the... The most intense ion is set to 100 % for all the occurring! Exposure is due to radon resulting atomic mass unit ( amu ) 217 and. Uses of nuclear industry – ∆H mass, and more at BYJU'S more... Neutrons ( blue ) rarely occurs in the atomic structure isotopes are:!, respectively χ, is a legal statement that explains what kind of information from this website usually differs is. More difficult to measure than ionization energies is 217 °C and its boiling... 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