The SO2 Lewis Structure is a graphical representation of the molecule’s electron distribution. To draw the SO2 Lewis Structure, the valence electrons of the sulfur and oxygen atoms are considered, and the electrons are arranged to minimize their repulsion. In the SO2 Lewis Structure, the sulfur atom is placed in the center, and the two oxygen ...Lewis Structures. A Lewis Structure is a representation of covalent molecules (or polyatomic ions) where all the valence electrons are shown distributed about the bonded atoms as either shared electron pairs (bond pairs) or unshared electron pairs (lone pairs). A shared pair of electrons is represented as a short line (a single bond).To answer the questions, interpret the following Lewis diagram for AsO2-.1. For the central arsenic 6. Complete the Lewis structure for this species:CO2Enter the total number of valence electrons in the 7. A Lewis structure ofDraw a Lewis structure for SO2 in which the central S atom obeys the octet rule; and answer the following questions based on your drawing: The number of unshared pairs (lone pairs) on the central S atom is: The central S atom forms single bonds. The central S atom forms double bonds.2. ) Lewis Structure, Hybridization. Sulfur dioxide molecule contains one sulfur atom and two oxygen atoms. We will construct the lewis structure of SO 2 molecule by following VSEPR theory rules and considering stability of intermediate structures. After obtaining the lewis structure of SO 2, we can determine the hybridization of atoms.2. Each hydrogen atom (group 1) has one valence electron, carbon (group 14) has 4 valence electrons, and oxygen (group 16) has 6 valence electrons, for a total of [ (2) (1) + 4 + 6] = 12 valence electrons. 3. Placing a bonding pair of electrons between each pair of bonded atoms gives the following: Six electrons are used, and 6 are left over.Step #4: Complete the octet (or duplet) on outside atoms. If the valence electrons are left, then put the valence electrons pair on the central atom. Don’t worry, I’ll explain! In the Lewis structure of HO2, the outer atoms are hydrogen atoms as well as oxygen atom. Hydrogen already has a duplet (see below image).Writing Lewis Structures with the Octet Rule. For very simple molecules and molecular ions, we can write the Lewis structures by merely pairing up the unpaired electrons on the constituent atoms. See these examples: For more complicated molecules and molecular ions, it is helpful to follow the step-by-step procedure outlined here.Complete the Lewis structures of these molecules by adding multiple bonds and lone pairs. Do not add any more atoms. (a) the amino acid serine: (b) urea: (c) pyruvic acid: (d) uracil: (e) carbonic acid: A compound with a molar mass of about 28 g/mol contains 85.7% carbon and 14.3% hydrogen by mass. Write the Lewis structure for a molecule of ...find all lewis structures, electron and molecular geometries and hybridization of. 1. SF3+ 2. AsO2-3. F2CO. 4. SO3. 5. H2SeA step-by-step explanation of how to draw the AsO4 3- Lewis Dot Structure.For the AsO4 3- structure use the periodic table to find the total number of valenc...Step 1: Count the total number of valence electrons present in the molecule/ion. For sulfate ions, we have one molecule of sulfur and four molecules of oxygen. Sulfur and oxygen both belong to the same group in the periodic table ( the chalcogen family) and have six valence electrons each. total valence electrons in SO42- = 6*1 + 6*4 +2 = 32.Step #1: Calculate the total number of valence electrons. Here, the given molecule is SO2 (sulfur dioxide). In order to draw the lewis structure of SO2, first of all you have to find the total number of valence electrons present in the SO2 molecule. (Valence electrons are the number of electrons present in the outermost shell of an atom).H2CO Lewis Structure, Molecular Geometry, Hybridization, and MO Diagram. It is an organic compound with the molecular formula of H2CO and is classified as an aldehyde. Aldehydes are chemicals having the functional group -HCO- in their molecules and formaldehyde is the lowest member of this group with a single carbon atom.The nobr Lewis structure is a diagrammatic representation of the arrangement of atoms and electrons in a molecule. It was developed by Gilbert N. Lewis in the early 20th century and is widely used in chemistry to understand the bonding and structure of molecules. The Lewis structure consists of symbols representing atoms and lines representing bonds between them.Step 1. Given: The molecule S O 2. To find: The Lewis structure of S O 2 where all atoms obey the octet rule, and the fo... View the full answer Step 2. Unlock. Step 3. Unlock.A Lewis Structure is a very simplified representation of the valence shell electrons in a molecule. It is used to show how the electrons are arranged around individual atoms in a molecule. Electrons are shown as "dots" or for bonding electrons as a line between the two atoms.Lewis structure of a water molecule. Lewis structures - also called Lewis dot formulas, Lewis dot structures, electron dot structures, or Lewis electron dot structures (LEDs) - are diagrams that show the bonding between atoms of a molecule, as well as the lone pairs of electrons that may exist in the molecule. A Lewis structure can be drawn for any covalently bonded molecule, as well as ...structure. To draw the Lewis structure for SO (sulfur monoxide), we need to consider the valence electrons of sulfur and oxygen.Sulfur is in Group 6A and has 6 valence electrons, while oxygen is in Group 6A and also has 6 valence electrons. In total, we have 12 valence electrons to distribute.. To distribute the electrons, we start by placing a single bond between sulfur and oxygen.The first two Lewis structures that can be drawn for #SO_2# will be. All 18 valence electrons are accounted for - 6 electrons from 3 bonds and 10 electrons distributed as lone pairs on the three atoms. A couple of important things to notice here. These two resonance structures are equivalent and will contribute equally to the hybrid structure.Question: To answer the questions, interperet the following lewis diagram for AsO2-1. for the central Arsenic atom:# of non-bonding electrons _____# of bonding electrons _____total # of electrons2. the central Arsenic atom ___ (options a b or c)A. Obeys octet ruleB. Has less than one octetC. HasStep #1: Calculate the total number of valence electrons. Here, the given molecule is CH2O. In order to draw the lewis structure of CH2O, first of all you have to find the total number of valence electrons present in the CH2O molecule. (Valence electrons are the number of electrons present in the outermost shell of an atom).Step 1. Sulfur ( S) is in Group 16 of the periodic tab... Draw the Lewis structure for the sulfur dioxide (SO2) molecule. Be sure to include alli resonance structures that satisfy the octet rule Il resonance structures that satisfy the octet rule. Add atom symbol , I ←→ 2.Are you on the hunt for the best deals and sales at John Lewis UK? Look no further. In this shopper’s guide, we’ll explore the top ways to save money and find great bargains at thi...Now in the SO2 molecule, you have to put the electron pairs between the sulfur atom (S) and oxygen atoms (O). This indicates that the sulfur (S) and oxygen (O) are chemically bonded with each other in a SO2 molecule. Step 4: Make the outer atoms stable. Place the remaining valence electrons pair on the central atom.Computed by PubChem 2.2 (PubChem release 2021.10.14) Dates. Create: 2005-06-23. Modify: 2024-05-25. Description. Arsenate (2-) is an arsenate ion resulting from the removal of two protons from arsenic acid. It is a conjugate base of an arsenate (1-).Arsenenite | AsO2 | CID 158274 - structure, chemical names, physical and chemical properties, classification, patents, literature, biological activities, safety ...Question: B. The Lewis diagram for AsO2 is: :0-as=0 Recall that for predicting geometry, double and triple bonds count as only one electron pair region. The electron-pair geometry around the As atom in AsO2 is trigonal plantar There are unshared pair (s) around the central atom, so the geometry of the AsO2 molecule is bent. There are 2 steps to ...1What is the total number of valence electrons in the Lewis structure of AsO2 electrons 2 Draw a Lewis structure for AsO2 or formal charges in your drawing. Do not include …Lewis structures can be drawn for polyatomic ions as well. In such instances, the valence electron count must also consider the ion charge. When the polyatomic ion is an anion (a negative ion), one must consider adding electrons to the valence electron count. After all, a negative ion has extra negative electrons in it (compared to its protons ...Question: What is the total number of valence electrons in the Lewis structure of SeBr20? electrons Submit Draw a Lewis structure for SeBr,O Do not include overall ion charges or formal charges in your drawing. If the species contains oxygen, do not draw double bonds to oxygen unless they are nee central atom to obey the octet rule. . .A step-by-step explanation of how to draw the SO3 2- Lewis Structure (Sulfite Ion). For the SO3 2- Lewis structure the total number of valence electrons ...C has less than an octet. To answer the questions, interpret the following Lewis diagram for AsO2- 30-AS=0 1. For the central arsenic atom: The number of non-bonding electrons = The number of bonding electrons The total number of electrons VII 2. The central arsenic atom A. obeys the octet rule. B. has less than an octet.Are you on the hunt for the best deals and sales at John Lewis UK? Look no further. In this shopper’s guide, we’ll explore the top ways to save money and find great bargains at thi...The lewis structure for sulfur dioxide can be described by two resonance structures: so2 these resonance structures indicates that the select one: a. single bond is longer than the double bond, and the electronic distribution in the two sulfur-to-oxygen bonds differs. b. the sulfer-oxygen bonds are identical and roughly midway between a single and double bond in length and strength.Steps. To properly draw the CF 2 Lewis structure, follow these steps: #1 Draw a rough sketch of the structure. #2 Next, indicate lone pairs on the atoms. #3 Indicate formal charges on the atoms, if necessary. Let’s break down each step in more detail.Step 1. We follow the following steps to draw the Lewis structure of the given molecule. First... Draw the Lewis structure for SeoBr2 in the window below and then answer the questions that follow. Use the References to access important values if needed for this que • Do not include overall ion charges or formal charges in your drawing.Sulfur dioxide (SO2) Lewis dot structure, molecular geometry or shape, electron geometry, bond angle, formal charge, hybridization. SO 2 is the chemical formula for sulfur dioxide, colorless gas that is extremely useful in the chemical industry. The pungent, suffocating odor associated with a burning matchstick is because of SO 2.Complete the Lewis dot structure for H, SO (in which H is bonded to O). Complete the molecule by placing a sultur atom and an additional oxygen atom on the grid and. Here’s the best way to solve it. Complete the Lewis dot structure for AsO 33 - Complete the molecule by connecting arsenic and the oxygen atoms with the appropriate bonds.Study with Quizlet and memorize flashcards containing terms like The correct Lewis structure for BF3 would have exactly:, The Lewis structure for carbon monoxide is : C ≡O : This structures shows:, How many bonding electrons are in the Lewis structure of carbon monoxide, CO? and more.Our expert help has broken down your problem into an easy-to-learn solution you can count on. Question: Draw the most important Lewis structure for SO2 and then answer the following questions. The underlined atom is the central atom. All other atoms are bonded directly to the central atom. (a) What is the electron-group geometry, according to ...Do not consider ringed structures. Draw a Lewis structure for SO2 in which all atoms have a formal charge of zero. Explicitly showing the zero charges is optional. Do not consider ringed structures. There are 2 steps to solve this one. Expert-verified.One can draw the 3-dimensional structure of an atom once they have the Lewis Structure of an atom. The 3-dimensional geometrical structure of ammonium, NH4+ is referred to as Tetrahedral. Nitrogen, having 5 valence shell electrons, along with 4 from Hydrogen, should have had 9 electrons. But the + sign decrees that NH4+ has 8 valence shell ...122.920 g/mol. Arsenite (3-) is an arsenite ion resulting from the removal of all three protons from the hydroxy groups of arsenous acid. It is an arsenite ion and a trivalent inorganic anion. It is a conjugate base of an arsenite (2-). See also: potassium arsenite anhydrous (active moiety of); Cupric arsenite (is active moiety of); Quinine ...Drawing the Lewis Structure for SO 2. The Lewis structure for SO 2 requires you to place more than 8 valence electrons on Sulfur (S). You might think you've got the correct Lewis structure for SO 2 at first. Remember, Sulfur is in Period 3 and can hold more than 8 valence electrons. You'll want to calculate the formal charges on each atom to ...Dec 9, 2019 · Valence electrons: 6 from S. 6 from each O x 2 = 12. Total valence electons =18. S is the center atom and has 2 O atoms attached. The S has 1 lone pair. One of the O atoms is double bonded to the S atom and this O atom has 2 lone pairs. The other O atom is singly bonded to the S atom, and it has 3 lone pairs. All atoms obey the octet rule.Due to the presence of 4 electron domains and its steric number being 4, the hybridization of SCl2 is given by sp3. SCl2 has a bent molecular structure and a tetrahedral electronic shape. It has bond angles of 103°. The chemical formula SCl2 represents Sulfur Dichloride. It is the simplest form of Sulfur Chloride and exists as a cherry-red ...References Draw the Lewis structure for PFs in the window. Here's the best way to solve it. Calculate the total number of valence electrons present in XeF4. A …. Draw the Lewis structure for XeF4 in the window below and then answer the questions that follow. Do not include overall ion charges or formal charges in your drawing.A brief overview of lewis dot structures.PubChem CID. 544. Structure. Molecular Formula. AsO3-3. Synonyms. arsorite. 15502-74-6. Arsenite ion. Trisoxylatoarsine. arsenite (3-) View More... Molecular Weight. 122.920 …Let us determine the Lewis structures of SiH 4, CHO − 2, NO +, and OF 2 as examples in following this procedure: Determine the total number of valence (outer shell) electrons in the molecule or ion. For a molecule, we add the number of valence electrons on each atom in the molecule: + SiH 4 + Si: 4 valence electrons/atom × 1 atom = 4 +H: 1 ...1 What is the total number of valence electrons in the Lewis structure of AsO2? electrons 2 Draw a Lewis structure for AsO2- . Do not include overall ion charges or formal charges …SO42- Lewis Structure. The Lewis Structure of any molecule helps to understand the bonding of atoms in the structure. Apart from that, it also helps to know the molecular shape, polarity, and other properties of the molecule. Generally, while forming bonds with other atoms, every atom tries to follow an octet rule that states that an atom must ...1 What is the total number of valence electrons in the Lewis structure of AsO2? electrons 2 Draw a Lewis structure for AsO2- . Do not include overall ion charges or formal charges in your drawing. • If the species contains oxygen, do not draw double bonds to oxygen unless they are needed in order for the central atom to obey the octet rule.Draw the best Lewis structure for SO 2 by filling in the bonds, lone pairs, and formal charges. (Assign bonds, lone pairs, radical electrons, and atomic charges where appropriate.) INCORRECT ANSWER: My answer was marked incorrect for the reason "Recall that in an octet-rule compliant Lewis structure, there can only be 8 electron groups surrounding the central atom".Draw the Lewis structure for Aso, in the window below and then answer the questions that follow. • Do not include overall ion charges or formal charges in your drawing. Do not …Question: Draw a Lewis structure for SO2 in which all atoms obey the octet rule. Show formal charges. Do notconsider ringed structures. Draw a Lewis structure for SO2 in which all atoms obey the octet rule. Show formal charges. Do notconsider ringed structures. There are 2 steps to solve this one.PCl 2- Lewis structure. PCl 2- has one phosphorus atom and two chlorine atoms. In PCl 2- Lewis structure, there are two single bonds around the phosphorus atom, with two chlorine atoms attached to it. Each chlorine atom has three lone pairs, and the phosphorus atom has two lone pairs. Also, there is a negative (-1) charge on the ...Long Lewis Ford has been serving the city of Hoover, Alabama for years, providing car shoppers with top-notch vehicles and exceptional customer service. If you’re in the market for...Step 1. Lewis structure is the simple representation of the valence shell electrons in a molecule. In Lewis ... View the full answer Step 2. Unlock. Step 3. Unlock. Step 4. Unlock.A video explanation of how to draw the Lewis Dot Structure for Sulfur Dioxide, along with information about the compound including Formal Charges, Polarity, ...Here are the steps I follow when drawing a Lewis structure. > 1. Decide which is the central atom in the structure. That will normally be the least electronegative atom ("S"). 2. Draw a skeleton structure in which the other atoms are single-bonded to the central atom: "O-S-O". 3. Draw a trial structure by putting electron pairs around every atom until each gets an octet. In this editor, I will ...The Lewis structure of the methane (CH4) molecule is drawn with four single shared covalent bonds between the carbon and hydrogen atoms each. Moreover, as there exist sigma bonds only and one 2s and three 2p orbitals of the carbon produce four new hybrid orbitals, the hybridization of CH4 is sp3. It is interesting to realize that irrespective ...The formal charge is the "charge" an element would have in a molecule or ion if all of the bonding electrons were shared equally between atoms We can draw three inequivalent Lewis structures for carbonyl sulfide , SCO. The concepts of formal charge and electronegativity can help us choose the structure that is the best representation. 1.There are equivalent two resonance structures NO2-, the nitrite ion. We start with a valid Lewis structure and then follow these general rules.-Resonance for...Steps of drawing AsO2- lewis structure. Step 1: Find the total valence electrons in AsO2- ion. In order to find the total valence electrons in AsO2- ion, first of all you should know the valence electrons present in the arsenic atom as well as oxygen atom. (Valence electrons are the electrons that are present in the outermost orbit of any atom.)PCl4+ lewis structure has 32 valence electrons and 12 lone pair electrons. It has complete octets of all P and Cl atoms. It has a +1 formal charge on the central P atom and zeroes formal charge on all 4 Cl atoms. It has a tetrahedral shape, sp3 hybridization of central P atoms, and a bond angle of 109.5 0.10.1: Lewis Structures and the Octet Rule is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by LibreTexts. Valence electronic structures can be visualized by drawing Lewis symbols (for atoms and monatomic ions) and Lewis structures (for molecules and polyatomic ions). Lone pairs, unpaired electrons, and ….PCl4+ lewis structure has 32 valence electrons and 12 lone pair electrons. It has complete octets of all P and Cl atoms. It has a +1 formal charge on the central P atom and zeroes formal charge on all 4 Cl atoms. It has a tetrahedral shape, sp3 hybridization of central P atoms, and a bond angle of 109.5 0.Lewis structure of HCO2- (or CHO2-) contains one double bond between the Carbon atom (C) & one Oxygen atom (O) and the rest other atoms are single bonded with each other. The Carbon atom is at the center and it is surrounded by 2 Oxygen atoms and one Hydrogen atom. The single bonded Oxygen atom has -1 formal charge.Formal charge on Sulfur atom = 6 - 2 -6 / 2 = 6 - 2 - 3 = 6 - 5 = +1. ∴ The formal charge on the S-atom in SO2 resonance structures is +1. For double-bonded oxygen atom. Valence electrons of oxygen = It is present in Group VI-A = 6 valence electrons. Bonding electrons = 1 double bond = 4 electrons. Non-bonding electrons = 2 lone ...A step-by-step explanation of how to draw the SO3 Lewis Dot Structure (Sulfur trioxide).For the SO3 structure use the periodic table to find the total number...The azide ion (N3-) is very reactive although it is isoelectronic with the very stable CO2 molecule. This reactivity is reasonable considering that A. a Lewis structure cannot be written for the azide ion that has nitrogen formal charges of zero. B. there are resonance structures for azide ion but not for carbon dioxide. C. there is no valid Lewis structure possible for the azide ion. D ...The S2O Lewis structure refers to the arrangement of atoms and electrons in a molecule of sulfur dioxide.Sulfur dioxide is a chemical compound composed of one sulfur atom and two oxygen atoms.The Lewis structure helps us understand the bonding and electron distribution within the molecule.In the S2O Lewis structure, the sulfur atom is in the center, surrounded by two oxygen atoms.The Lewis Structure for water is useful because it allows to determine the molecular geometry and the polarity of the molecule. Because of the two lone pairs, H 2 O will have a bent molecular geometry and it will be a polar molecule. Remember that Hydrogen only needs two electrons to have a full outer shell. Video: Drawing the Lewis Structure ...A step-by-step explanation of how to draw the H2O Lewis Dot Structure (Water).For the H2O structure use the periodic table to find the total number of valenc...Apr 5, 2024 · April 5, 2024 by Deep. The information on this page is fact-checked. Lewis structure of SO 2 | Image: Root Memory. The Lewis structure of SO2 contains two double bonds, with sulfur in the center, and two oxygens on either side. There are two lone pairs on each oxygen atom, and one lone pair on the sulfur atom. Lewis structure of SO2.This widget gets the Lewis structure of chemical compounds. Get the free "Lewis Structure Finder" widget for your website, blog, Wordpress, Blogger, or iGoogle. Find more …find all lewis structures, electron and molecular geometries and hybridization of. 1. SF3+ 2. AsO2-3. F2CO. 4. SO3. 5. H2SeChemical Structure Depiction Full screen Zoom in Zoom out PubChem 1.2 3D Conformer PubChem 1.3 Crystal Structures COD records with this CID as component 1546250 2107126 4066764 4066765 4072452 4086520 4106638 ...SO2 Lewis Structure Setup Step-2: SO2 Valence Electrons. Now we have to count total number of SO2 valence electrons. S = 6. 2×O=6×2=12. So, the total number of valence electrons for SO2 molecule is eighteen ( 6+12= 18) . Here is the another way to find out SO2 valence electrons. Sulfur is the element of group 6A,so it has six valence ...A step-by-step explanation of how to draw the SO2 Lewis Structure (Sulfur Dioxide) Note: From an experimental view (using x-ray crystallography or someth...In this video, we'll learn about the Lewis Structure of Sulphur Dioxide - SO2. This structure is key to understanding the chemistry of Sulphur Dioxide. We'll...Today in this video, we will determine the Lewis dot structure for sulphur dioxide, having a chemical formula of SO2. It comprises one sulphur atom and two O...Chemistry questions and answers. 1 What is the total number of valence electrons in the Lewis structure of ClO2? electrons 2 Draw a Lewis structure for CI021 . Do not include overall ion charges or formal charges in your drawing. . If the species contains oxygen, do not draw double bonds to oxygen unless they are needed in order for the central ...As far as I understand $\ce{SO4^2-}$ structure, sulfur makes two coordinate bonds with two oxygen atoms and two double bonds are formed with oxygen after sulfur expands it's valance shell to 6. At this point calculating formal charge of those two coordinate bonded oxygen gives total formal charge of −2 and the formal charge on $\ce S$ and the ...Chemistry questions and answers. Draw the Lewis structure of AsO2 showing all lone pairs Identify the molecular geometry of AsO2 linear Select Draw Rings More Erase square planar 3- octahedral As O tetrahedral trigonal bipyramidal trigonal pyramidal see-saw bent T-shaped square pyramidal trigonal planar What are the approximate bond angles in ...Chemistry questions and answers. Draw the Lewis structure of AsO2 showing all lone pairs Identify the molecular geometry of AsO2 linear Select Draw Rings More Erase square planar 3- octahedral As O tetrahedral trigonal bipyramidal trigonal pyramidal see-saw bent T-shaped square pyramidal trigonal planar What are the approximate bond angles in ...The above O 3 resonance structures are real, as opposed the the resonance hybrid, which is not. The resonance hybrid means the average of the above two resonance structures. This average Lewis structure is, by definition, a mathematical artifact that is not real. We could say, on average, there are 1.5 bonds going left and 1.5 bonds going right.Our expert help has broken down your problem into an easy-to-learn solution you can count on. Question: Draw a Lewis structure for SO2 in which all atoms obey the octet rule. Show formal charges. Do not consider ringed structures. There are 2 steps to solve this one.However in reality SO2 or any molecule that has resonance structures exists as an average of its structures. For SO2 the first two structures fit the octet rule for each atom but because sulfur is in the third period it stands that the expanded octet rule could apply as the 3d orbital might play a role in bonding.There are many well-known differences in the physical and chemical properties of ozone (O3) and sulfur dioxide (SO2). O3 has longer and weaker bonds than O2, whereas SO2 has shorter and stronger bonds than SO. The O-O2 bond is dramatically weaker than the O-SO bond, and the singlet-triplet gap in SO …John Lewis was not just a civil rights icon; he was also a remarkable leader who left a las, Chemistry questions and answers. a. Draw the most stable Lewis structure of AsO3-1 b. Dra, SO2 Lewis Structure. Step 1 - Figuring out the total , Solution. Lewis structure of BeI A 2. View the full answer Step 2. Unlock. An, The total number of valence electrons in the lewis structure of AsO₂⁻ is 18. The structure is attach, Step #1: Calculate the total number of valence electrons. Here, the g, Question: Draw a Lewis structure for the resonance form of Aso, with the lowest possible formal charges. Include any non, Feb 12, 2021 · The SO2 Lewis structure would consist of two ox, H2CO Lewis Structure, Molecular Geometry, Hybridization, and MO , A step-by-step explanation of how to draw the Sulfate Ion Lew, 1 Answer. There are 5 × 6 + 2 = 32 electrons to dist, Craig Beals shows how to draw the Lewis Structure for the Sulfu, Chemical Engineering questions and answers. Consider, A step-by-step explanation of how to draw the SO2 Lewis , Lewis dot structures represent atoms with their atomic sy, John Lewis is one of the UK’s leading department sto, The formal charges of the SO 2 with the single bon, Step 1: Determine the total number of valence electrons. S.