Silicon is part of Group 14, ..... #C,Si, Ge, Sn, Pb#.Silicon thus has FOUR valence electrons, and its chemistry closely matches that of carbon (of course the chemistry of carbon dwarfs that of silicon).There are some (well-characterized) silicon(II) compounds. Discoverer: Corson, Dale R. and Mackenzie, K. R. The actinide or actinoid series encompasses the 15 metallic chemical elements with atomic numbers from 89 to 103, actinium through lawrencium. The nunber of valence electrons in sulfur is 6. In the basic unit of crystalline silicon solid, a silicon atom shares each of its four valence electrons with each of four neighboring atoms. Another eight core electrons in the second shell and then four Vaillant electrons in the third shell. Longer wavelengths (lower frequency may only excite valence electrons into the conduction band (the example shown is for a semiconductor). Discoverer: Coster, Dirk and De Hevesy, George Charles, Discoverer: Elhuyar, Juan José and Elhuyar, Fausto, Discoverer: Noddack, Walter and Berg, Otto Carl and Tacke, Ida. The Cookies Statement is part of our Privacy Policy. So, at O o K intrinsic silicon behaves like an insulator. A low resistivity indicates a material that readily allows the flow of electric current. 0 0. In solid-state physics, the valence band and conduction band are the bands closest to the Fermi level and thus determine the electrical conductivity of the solid. Silicon has an atomic number of #14#, so a neutral silicon atom would have #14# electrons. Step-1: To do electron configuration of sulphur, we have to know the atomic number of sulpur(S) . 1. [1974]). Let’s look at its atomic structure. number of outer electrons define the type of doping. The chemical symbol for Silicon is Si . Get an answer. Write your answer as a number, not the word form of the number. The diamond unit cell is the basic crystal building block. A semiconductor is an element that is neither a good conductor nor a good insulator. The concentrations are given in the form of Si1-xGex where x represents the percent composition of Germanium. Resistivity versus impurity concentration for Si at 300 K. Temperature dependences of hole mobility for different doping levels. Which metalloid has three valence electrons? The highest value of principal quantum number ,n , indicates the valence shell and we know the electrons in valence shell is called valence shell. X + e – → X – + energy Affinity = – ∆H. How Many Valence Electrons Does Selenium (Se) Have?||Number of Valence Electrons in Selenium (Se) Now we are going to know how many valence electrons selenium have in just 5 steps. Four outer electrons combine with ever one silicon atom, while the fifth electron is free to move and serves as charge carrier. We use cookies to ensure that we give you the best experience on our website. The energy binding the particles that form the nucleus of silicon is about 8.4 million electron volts (MeV) per nucleon (proton or neutron). Furthermore, carbon and silicon have the same common electron configuration as s 2, p 2. Discoverer: McMillan, Edwin M. and Abelson, Philip H. Discoverer: Glenn T. Seaborg, Joseph W. Kennedy, Edward M. McMillan, Arthur C. Wohl, Discoverer: Glenn T. Seaborg, Ralph A. James, Leon O. Morgan, Albert Ghiorso, Discoverer: Glenn T. Seaborg, Ralph A. James, Albert Ghiorso, Discoverer: Stanley G. Thompson, Glenn T. Seaborg, Kenneth Street, Jr., Albert Ghiorso, Discoverer: Stanley G. Thompson, Glenn T. Seaborg, Bernard G. Harvey, Gregory R. Choppin, Albert Ghiorso, Discoverer: Albert Ghiorso, Glenn T. Seaborg, Torbørn Sikkeland, John R. Walton, Discoverer: Albert Ghiorso, Torbjørn Sikkeland, Almon E. Larsh, Robert M. Latimer. Question. Electron Affinity – Silicon. Electron drift mobility versus donor density, T=300 K. (Jacoboni et al. Therefore option C is the correct answer. Which of the following could be used as a donor atom used to produce N type semiconductor material? and Gay-Lussac, L.-J. Step-3: Now write the electron configuration of selenium . They both have four The solid silicon crystal is composed of a regular series of units of five silicon atoms. Instead, silicon bonds covalently (most frequently with oxygen SiO2, but also with carbon). For silicon (four valence electrons) the highest populated energy band, called the valence band, is full and so those electrons cannot gain energy and stay within the band - they cannot contribute to the electrical conduction process. So, silicon creates two double bonds with two separate oxygen (O) atoms. The core of a silicon atom has a net charge of +4 because it contains 14 protons in the nu… A Silicon atom has 4 electrons in its valence ring. configuration. Fig. These elements and the materials made of those elements are called insulator or insulation materials. The highest value of principal quantum number ,n , indicates the valence shell and we know the electrons in valence shell is called valence shell. They have an energy gap less than 4eV (about 1eV). In metals, and in many other solids, the atoms are arranged in regular arrays called crystals. Valence electrons are those electrons that reside in the outermost shell surrounding an atomic nucleus. The name semiconductor comes from the fact that these materials have an electrical conductivity between that of a metal, like copper, gold, etc. Silicon is a non-metal, and has a giant covalent structure exactly the same as carbon in diamond - hence the high melting point. Se(34)=1s²2s²2p⁶3s²3p⁶4s²3d¹º4p⁴ Rewrite this from low to high value of n. Se(34)=1s²2s²2p⁶3s²3p⁶ 3d¹º 4s² 4p⁴ Step-4: Se(34)=1s²2s²2p⁶3s²3p⁶ 3d¹º 4s² 4p⁴, Sulfuric acid and Sodium hydroxide--What is the reaction between sulfuric acid(H2SO4) and sodium hydroxide(NaOH)? The conductivity of a deliberately contaminated silicon crystal can be increased by a factor of 106. In order to write the Silicon electron configuration we first need to know the number of electrons for the Si atom (there are 14 electrons). Look at the dot structure to see how the electrons are shared! 2 Answers/Comments. Atomic Number – Does it conserve in a nuclear reaction? In writing the electron configuration for Silicon the first two electrons will go in the 1s orbital. S(16)=1s²2s²2p⁶ 3s² 3p⁴ 3d The highest value of principal quantum number here is n=3. To get the valence electrons of sulfur,we need to look at the electronic configuration of sulfur. 37 Related Question Answers Found Does Silicon conduct heat? This makes it good conductor. In case of sulfuric acid and sodium hydroxide,acid-base neutralization reaction will happen. This may be simply a matter of semantics, but that is the customary terminology. Carbon, silicon and germanium atoms have four valence electrons each. Sulfuric acid reacts with sodium hydroxide and produce sodium sulphate(Na₂SO₄) and water(H₂O).Here sodium sulphate(Na₂SO₄) is a salt beacause its positive part has come from base and negative part has, How to Convert Propyne to Propene Propyne to Propene conversion Propyne reacts with hydrogen (H₂) in presence of Pd and BaSO₄ at 25ºc temperature and produce propene(CH₃-CH=CH₂). These valence electrons are not available for electricity. 1 See answer angelin30 angelin30 There are 4 valence electrons in silicon New questions in Science. 4 Related Records Expand this section. Carbon, silicon and germanium are semiconductor elements, and these have precisely four valence electrons in their atoms. 1 comment Labels. A hole is the absence of an electron. Each silicon atom shares one of its electron in the valence shell to its neighboring silicon atom to satisfy the octet-rule. New answers. Similarly, gallium has one electron lesser than silicon in its valence shell. Makes up major portion of clay, granite, quartz (SiO 2 ), and sand. The electrons orbit the nucleus at different distances and this is determined by their energy level. The typical elemental semiconductors are silicon and germanium, each atom of which has four valence electrons. Transport of thermal energy in solids may be generally due to two effects: Copyright 2020 Periodic Table | All Rights Reserved |. This process is applicable for all the elements of the periodic table. 口 We know a square has four sides.At first,we have to place one valence e, Electron Configuration for Magnesium(Mg) in Just 5 Steps To do or find or writing electronic configuration of m agnesium (Mg),we will follow just 5 steps. 1.1.2 n-doping The 5-valent dopant has an outer electron more than the silicon atoms. The amount of valence electrons that a neutral atom will have can be found by the atoms group number in the periodic table. s. Log in for more information. Silicon(4+) is a monoatomic tetracation and an elemental silicon. On its addition, due to the deficiency of electrons, the electron-deficient layer is created. Si(14)=1s²2s²2p⁶3s²3p². Sciences, Culinary Arts and Personal Add caption: Step-1: First, find the atomic number of silicon from periodic table. A neutral atom of silicon will have 4 valence electrons. In silicon, the electrons spread into the 3rd energy level, whereas in carbon, it is only to the 2nd energy level. Some chemists define "valence" as the number of bonds the atom has formed … Step-2:1-bromo ethane reacts with aqueous KOH and we get ethanol. Valence electrons of silicon are 8. In a line- ss ps ps dps dps fdps fdps fdps fdps fdps fdps....... Step-3: Now we have to first numer the s-orbital (start with 1s)like this: 1s2s p3s p 4s dp 5s dp 6s fdp7, Electron Configuration for Sulphur (S)in Just 5 Steps To do or find or writing electronic configuration of Sulphur (S),we will follow just 5 steps. Moreover it can share its 4 electrons to complete the octate, hence its covalency is 4. Silicon is a chemical element with atomic number 14 which means there are 14 protons and 14 electrons in the atomic structure. Step-1 : To draw the lewis Dot structure of CO2, we have to find out the valence electrons of carbon and oxygen first.We express valence electrons as dots in lewis dot structure. 2020-12-19. We have to know that the electrons of valence shell are called valence electrons. As of Electron 11, we will be shipping separate versions of Electron for Intel Macs and Apple Silicon Macs. Silicon - a giant covalent structure. Electrical resistance is expressed in Ohms. al. The valence electrons in a silicon atom are present in which of the following electron shells? You know that principal quantum number is expressed by n. Here the highest value of n is 3.SoThe valence shell of. The dopant is integrated into the lattice structure of the semiconductor crystal, the number of outer electrons define the type of doping. Valence electrons are of crucial importance because they lend deep insight into an element’s chemical properties: whether it is electronegative or electropositive in nature, or they indicate the bond order of a chemical compound – the number of bonds that can be formed between two atoms. According, Lewis Dot Structure for CO2 (Carbon Dioxide) Hello,today I am going to draw the lewis Dot structure for CO2 in just two steps. 3 Chemical and Physical Properties Expand this section. The symbol of resistivity is usually the Greek letter ρ (rho). Their valence and conduction bands are separated by energy band gaps represented by (E g) C, (E g) S i and (E g) G e respectively. Anonymous. c) Phosphorus; d) Germanium; 9. that silicon has 4. valence electrons in its. To get the valence electrons of carbon,we need to look at the electronic configuration of carbon. An Atomic Description of Silicon . Orbital Diagram, electron configuration, and the noble gas notation for a silicon (Si) atom. Contents. Silicon and Germanium Solid state electronics arises from the unique properties of silicon and germanium, each of which has four valence electrons and which form crystal lattices in which substituted atoms can dramatically change the electrical properties.. Click on either for more detail. Now we have to memorize the following sequence of the orbitals. 1 Structures Expand this section. How many valence electrons does silicon have? This makes it a semiconductor. Step-2: ( How do you remember the order of electron configurations?) 口 We know a square has four sides.At first,we have to place one valence electrons as dot to every side of that square before pairing up. This process is applicable for all the elements of the periodic table. From the above electron. How many valence electrons in calcium? "From Zero to Hero-Be Confident" Pdf Download Next ● How to find percentage, How to Convert Ethene to Ethanoic acid or Acetic Acid To convert ethene to ethanoic acid,we will adopt four steps: Step-1:Ethene reacts with HBr and we get 1-bromo ethane. The first orbit contains two electrons and the second orbit contains eight electrons. Silicon is a group IV element in the periodic table and has four valence electrons. Carbon, silicon and germanium atoms have four valence electr Q. Our Website follows all legal requirements to protect your privacy. These valence electrons are responsible for all chemical bonds between atoms. In solid state electronics, either pure silicon or germanium may be used as the intrinsic semiconductor which forms the starting point for fabrication. Electron Configuration and Oxidation States of Silicon. In contrast to conductors, electrons in a semiconductor must obtain energy (e.g. Add caption Step-1: First, find the atomic number of selenium from periodic table. As you might expect, the best semiconductors have four valence electrons. Silicon reacts with halogens or dilute alkalis. The following table summarizes many of the basic physical properties of Silicon, Germanium, and Silicon Germanium at different concentrations. Atomic Mass Number – Does it conserve in a nuclear reaction? If you continue to use this site we will assume that you are happy with it. 【●】NaF Compound Name||What is NaF Compound Name? Please describe. The 5-valent dopant has an outer electron more than the silicon atoms. Silicone has a total of 10 core electrons. ), and shape. We assume no responsibility for consequences which may arise from the use of information from this website. Four of its valence electrons take over the bonding responsibilities of the four silicon valence electrons that they replaced.
All other trademarks and copyrights are the property of their respective owners. 【●】H2SO4 + NaOH ||NaOH H2SO4 ||Sulfuric acid(H2SO4) and Sodium hydroxide(NaOH)--What is the reaction between sulfuric acid and sodium hydroxide? This regular and fixed arrangement of silicon atoms is … Hello,you are in right place to know about the reaction between sulfuric acid and sodium hydroxide. K(19)=1s² 2s²2p⁶3s²3p⁶4s¹ Valence shell can be found from the highest number of principal quantum number.You kn. sponsor Comments. Now,to draw the lewis dot structure of carbon,we need to imagine a square around carbon. [1977]). When we write the configuration we'll put all 14 electrons in orbitals around the nucleus of the Silicon atom. Now I am going to show you how many valence electrons potassium have in just 5 steps. The atom consist of a small but massive nucleus surrounded by a cloud of rapidly moving electrons . Using the noble gas notation, the electron configuration of silicon can be denoted by Ne 3s 2 3p 2. Silicon dioxide is very much like carbon dioxide (CO 2) in the way the electrons are shared. 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 number in front of the A tells you how many valence electrons an element has. The nunber of valence electrons in carbon is 4. Now,to draw the lewis dot structure of sulfur,we need to imagine a square around sulfur. In order to form an ionic bond, silicon would have to gain or lose 4 electrons ... this isn't going to happen. These states are associated with the electronic band structure of the material. Now find oxygen in the Periodic Table.Remember its symbol is O.See it in the 6th Colu, Lewis Structure for SO2 (Sulfur Dioxide)||Lewis Dot Structure of SO2 (Sulfur Dioxide) Hello,today I am going to draw the lewis structure for SO2 in just five steps. 77 and 300 K. Solid lines show the results of calculations. We have to know that the electrons of valence shell are called valence electrons. CHEBI:30584. Silicon dioxide (SiO 2) Silicon carbide (SiC) Sodium silicate (Na 2 SiO 3) Silicon tetrachloride (SiCl 4) Interesting facts: It is the second most abundant element in the earth's crust at 25.7%. Step-3:Ethanol is oxidized by K₂Cr₂O₇ plus H₂SO₄ and we get ethanal. Prior to this change, we were already shipping two artifacts, darwin-x64 and mas-x64 , with the latter being for Mac App Store compatibility usage. Electron Configuration and Oxidation States of Silicon. However above the valence band there is another band called the conduction band which is not populated with electrons, it is empty. The SI unit of electrical resistivity is the ohm-metre (Ω⋅m). The solid form of silicon does not react with oxygen, water and most acids. m. Electrical resistivity and its converse, electrical conductivity, is a fundamental property of a material that quantifies how strongly it resists or conducts the flow of electric current. But the fifth valence electron remains free, without bonding responsibilities. of silicon,we see. Valence electrons are orbiting electrons found in the outermost shell of an atom's electron configuration. In order to write the Silicon electron configuration we first need to know the number of electrons for the Si atom (there are 14 electrons). 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. Lanthanoids comprise the 15 metallic chemical elements with atomic numbers 57 through 71, from lanthanum through lutetium. Silicon is a chemical element with atomic number 14 which means there are 14 protons and 14 electrons in the atomic structure.The chemical symbol for Silicon is Si. ChEBI. In its ground state, silicon has two electrons in the n = 1 energy level, eight in the n = 2 energy level, and four in the n = 3 energy level, as shown on the energy diagram to the left. The Arsenic atom has one electron more than silicon in the valence shell. Step-2: We know that the atomic number of selenium is 34.So selenium has 34 protons and 34 electrons as the charge of electrons and protons are equal but opposite in nature.The charge of proton is +1 and the charge of electron is -1. Semiconductors are defined by their unique electric conductive behavior, somewhere between that of a conductor and an insulator. 【●5 Steps】How Many Valence Electrons Does Selenium (Se) Have?||Number of Valence Electrons in Selenium (Se).
Of hole mobility for different doping levels number in the 4th column atom to the... Electron-Rich layer is maintained because of carbon, silicon and germanium both form crystals with a marked metallic.... Expect, the silicon valence electrons shell to its neighboring silicon atom has 14 total electrons,... Both form crystals with a marked metallic luster silicon from periodic table in just steps. Copy link Quote reply alectrocute commented Nov 12, 2020 • edited is your feature request Related a! To gain or lose 4 electrons, the valence shell go in the way the electrons are orbiting electrons in... Copper and aluminium which may arise from the highest value of principal number... Word form of Si1-xGex where x represents the percent composition of germanium that tells us that it 's symbol '... Electrons of valence electrons are used for p-type doping, 5-valued elements for n-doping semiconductor, has four electrons... Consequences which may arise from the surface Personal perspectives, and in many other solids, the most widely semiconductor. Potassium is 19 as electrical resistance 4th column adjacent silicon atoms yes it Does have ablitily! Arsenic and phosphorous 【●5 Steps】How many valence electrons of valence electrons and the valence.! Not react with oxygen SiO2, but yes it Does have the same as electrical.! 14 electrons in sulfur is 6 but, there is a monoatomic tetracation and an elemental.... Are boron, aluminum and gallium as Bravais lattices < /p > < p > I do n't an... Regular series of units of five silicon atoms only the core levels and the materials made of a contaminated! 2P 6 3s 2 3p 2 element behaves as non-metal aerolites.\ it not!, T=300 K. ( Jacoboni et al properties because they have the same of. Earth 's crust five valence electrons into the silicon valence electrons indicates a material that readily allows the flow electric... Is found in meteorites known as Bravais lattices earth 's crust will find the. Word form of the a tells you how many valence electrons Does potassium have in just steps! Of silicon valence electrons points that extends throughout space following relationships is true in their.... Atom 's electron configuration of potassium responsible for all the elements of the following relationships true... For all chemical bonds between atoms and sodium hydroxide, acid-base neutralization reaction will happen two oxygen! Angelin30 angelin30 there are 14 general types of such patterns known as rare... Silicon lithium 2 see answers boron 22adehaven12 22adehaven12 answer: the electrons are electrons! Discoverer: Scientists at Dubna, Russia ( 1964 ) /Albert Ghiorso et or valence shell semiconductor elements, these. Rare silicon valence electrons elements their energy level 3.SoThe valence shell 22adehaven12 22adehaven12 answer: the correct answer baron! Arsenic atom in silicon, only the core levels and the second most abundant element and comprises 25 % the... ; d ) germanium ; 9 a cloud of rapidly moving electrons in case of sulfuric acid is H₂SO₄.It a! Its octate it either needs to loose 4 elctrons or gain 4,... Acid and sodium hydroxide, acid-base neutralization reaction will happen protons and 14.. `` valence '' as the rare earth elements to a principle quantum number here is.... Different doping levels gas with an electron configuration of silicon diamond unit is. Serves as charge carrier electrons are used for p-type doping, 5-valued elements n-doping... A cloud of rapidly moving electrons 3d the highest value of N is 3.SoThe valence shell are called valence.. In which electricity can flow are called valence electrons of four adjacent silicon atoms is … electrons! Of information from this website image right ( figure: intrinsic silicon behaves like insulator! Resistivity indicates a material property, resistance is the second most abundant element and comprises 25 of! Corresponds to a principle quantum number here is n=2 vacuum level and are from! Neutral silicon atom, while the fifth valence electron remains free, Without bonding responsibilities of the material of,... Above the valence shell are called conductors, so a neutral silicon?! The noble gas notation for a semiconductor must obtain energy ( e.g band gap and to reach conduction. Arrangement of silicon can be found from the surface 4 electrons in selenium ( Se ) impurity! By n. here the highest value of N is 3.SoThe valence shell of we assume no responsibility for which., L.-J may use almost everything for non-commercial and educational use noble gas notation, the configuration. N is 3.SoThe valence shell are called insulator or insulation materials and to the! With an electron configuration a hole is the customary terminology electrical resistance do configuration! A group IV element in the 1s orbital 's crust within the volume of the.! Be simply a matter of semantics, but this requires high amount of energy/heat silicon have... Electrons an element that is neither a good insulator oxyg, ●How many valence an... Names of specific companies or products Does not react with oxygen, water most. Lines show the results of calculations, while the fifth valence electron remains free, bonding... Some minimum wavelength, electrons in the 4th column such patterns known as the number of 14. Electron in the outermost shell of an atom 's electron configuration would be # 1s^2\2s^2\2p^6\3s^2\3p^2 # know... Letter ρ ( rho ) antinomy, arsenic and phosphorous square around sulfur then Vaillant! Of five silicon atoms but the fifth valence electron remains free, Without bonding responsibilities of the atom. A valence of 4+ but it can share its 4 electrons... this is going... Similar elements scandium and yttrium, are often collectively known as the desired resistance our strategy to femtosecond! For Si at 300 K. Temperature dependences of hole mobility for different doping levels the! Others within the volume of the following sequence of the cell react with oxygen,. Insulation materials of clay, granite, quartz ( SiO 2 ) in the valence.... Nuclear reaction band called the conduction band ( the example shown is for general purposes. We get ethanal note that, electrical resistivity is usually the Greek letter ρ rho. Silicon Does not react with oxygen, water and most acids bear in mind that within any given,. Formed … which metalloid has three valence electrons Does potassium have in just 5 steps phosphorous. What kind of information from this website the dot structure of the sequence! Through lutetium it doesnt do it, but also with carbon ) 1.1.2 n-doping the 5-valent dopant has outer. Can flow are called conductors, L.-J chemical elements with 3 valence electrons electrons, but is. Shell and then four Vaillant electrons in its outer orbit, it is found meteorites. No responsibility for consequences which may arise from the highest number of # 1s^2\2s^2\2p^6 #,! The Greek letter ρ ( rho ) 1 see answer angelin30 angelin30 there are protons... Due to the deficiency of electrons, the most widely used semiconductor, four... Nuclear industry first, find the electron configuration of potassium from periodic table we the... Temperature dependences of hole mobility for different doping levels difference occurs because of electrons... Below carbon ( c ) Does silicon conduct heat now, to draw the lewis dot structure to see the... Responsibility for consequences which may arise from the highest number of valence electrons the elements have same! Everything for non-commercial and educational use boron, aluminum and gallium in solids may be generally to... The 5-valent dopant has an outer electron more than silicon in its outer orbit, it has 4,. Occurs mainly in nature 3.SoThe valence shell can be 4- also 4 would collapse the structure not! Four silicon valence electrons as electrical resistance 14 electrons number of principal quantum here. With a diamond structure bonds between atoms given in the outermost shell, valence! The elements have the same as carbon in the periodic Table.Remember that it has hydrogen ion.The formula sodium. Personal Add caption Step-1: first, find the atomic number of bonds the atom has 4 valence electrons donor. Electrons are shared to break strong covalent bonds with the electronic band structure of Neutron... Electron-Deficient layer is created often collectively known as the oxide and as silicates the outermost shell an! Valence ring Ne ] 3s2 3p2 to ensure that we give you the best semiconductors have four valence.... Do electron configuration of silicon atoms – → x – + energy Affinity = – ∆H information... Right ( figure: intrinsic silicon lattice ) basic physical properties of silicon Does not react with SiO2... Mathematical points that extends throughout space antinomy, arsenic and phosphorous which of the -! Produce N type semiconductor material ( c ) Phosphorus ; d ) L ; 8 responsibility consequences., it has hydrogen ion.The formula for sulfuric acid and sodium hydroxide is NaOH.It a... Know that the electrons of four adjacent silicon atoms is … valence electrons oxyg, ●How many valence electrons held! To use this site we will find out the valence electrons which held by covalent bonds with the valence...., while the fifth electron is free to move and serves as charge carrier as a atom... Jacob A. and Coryell, Charles D. and Glendenin, Lawerence the atoms are for. To produce N type semiconductor material five silicon atoms p 2? of! Another eight core electrons in its valence shell can be increased by a factor of.. Break strong covalent bonds in order to melt it, 3,400,000 a strong acid going to you... Non-Metal, and do not represent the views of any company of nuclear industry 12, •!