What is Lewis structure: Definition and 47 Discussions

Lewis structures, also known as 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 coordination compounds. The Lewis structure was named after Gilbert N. Lewis, who introduced it in his 1916 article The Atom and the Molecule. Lewis structures extend the concept of the electron dot diagram by adding lines between atoms to represent shared pairs in a chemical bond.
Lewis structures show each atom and its position in the structure of the molecule using its chemical symbol. Lines are drawn between atoms that are bonded to one another (pairs of dots can be used instead of lines). Excess electrons that form lone pairs are represented as pairs of dots, and are placed next to the atoms.
Although main group elements of the second period and beyond usually react by gaining, losing, or sharing electrons until they have achieved a valence shell electron configuration with a full octet of (8) electrons, hydrogen (H) can only form bonds which share just two electrons.

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  1. nomadreid

    Central atoms in Lewis structures: basic question

    The two rules are Methods 1 and 3 in https://sciencing.com/how-to-name-covalent-compounds-13712167.html Given that the electronegativities of C, Si, N, P, S, O are approx. 2.5, 1.8, 3.0, 2.1, 2.5, , 3.5, resp., one of these rules has to give. Thanks.
  2. Faelyn

    Chemistry All possible resonance structures for SO4 2-

    So I know about the 6 stable resonance Lewis Dot diagrams for sulfate: As well as the unstable diagram that only has single bonds between the sulfur and oxygen atoms.But, is it possible for there to be other resonant structures with either 1 or 3 double bonds, even if they're more unstable? I...
  3. Z

    Chemistry How do we know ##BF_3## has Lewis structure but ##Al_2S_3## does not?

    The first thing we notice is that we have a metal and a nonmetal, so we would think about an ionic model. These elements form the ions ##Al^{3+}## and ##S^{2-}##. These ions form a lattice structure and we get an ionic crystal. But apparently no bond is perfectly ionic or covalent. The...
  4. L

    Which diagram of water molecules is correct?

    I've seen both types of diagrams when drawing covalent dot and cross diagrams. And some students that I teach said that the electrons should be on the circles. But I do know that this is actually showing the electron overlap and electron field and in reality electrons are not in circular orbits...
  5. S

    Chemistry Drawing resonance structure for this O-CH2 ion

    ion shown: My answer: the following is the answer of the question: I identified the major contributor correctly, but the resonance structures, but the second resonance I drew is missing in the answer sheet. Can anyone tell me why the second resonance structure is not part of the answer...
  6. S

    Chemistry Drawing resonance structure for SO42

    I was told that there are six resonance structures for SO42-, as shown below. I am wondering why this structure with single bonds is not one of the possible resonance. I understand that it is unfavorable as the formal charges are spread out over all four atoms, but shouldn't is still be a...
  7. nineteen

    Why do we have to memorize Lewis structures of ....

    Why do we have to memorize the structures of all the nitrogen oxides? Isn't there any way to understand about the Lewis structures of all the nitrogen oxides and their weird ways of making bonds?
  8. Physics345

    Drawing Lewis structure and structural formula

    Homework Statement Draw the Lewis structure and structural formula for: a) HCN b) SO3 2- Homework Equations none The Attempt at a Solution Did I do these correctly? Thanks!
  9. C

    Electron dot structure, Lewis structure

    Which is more correct, teaching the first two valence electrons as paired in the electron dot structure or teaching them as not pairing until forced.
  10. D

    How do I draw Lewis Structure Diagrams? +1 More

    Homework Statement : 2 Questions, sorry about this if It adds confusion. 1) How do I go about drawing Lewis Structure Diagrams? I've searched the web, but all I can find, even when they say it's a "Lewis structure" diagram is lewis dot diagrams. My teacher wants it in the specific form where...
  11. yecko

    Which Lewis Structure is the Most Stable?

    Homework Statement http://i.imgur.com/Jt3u2uo.png Homework Equations octet structure bond strength bond order The Attempt at a Solution I have no idea why the answer is b... after reading the book... thank you.
  12. A

    What is the Lewis structure of C3H5+ ion?

    Hi, For school, I have to give the Lewis structure of C3H5+ ion. There is a method explained, which is fairly easy, and has always worked. It has also worked for ions. However, this is the first time I have to give the Lewis structure of a positive ion.The valence of the C atom is 4 electrons...
  13. A

    Enflurane (CHFClCF2OCHF2) Lewis structure

    So I keep getting this problem wrong and I don't know what's wrong. The structure I came up with is attached. If anyone can help I'd really appreciate it!
  14. Titan97

    How can I find oxidation number of N in N2O?

    Homework Statement How can I find oxidation number of N in N2O using lewis dot structure? Homework Equations None The Attempt at a Solution Is the structure of N2O like this:
  15. S

    Lewis structure and thermochemistry problems

    Hi I have a few questions that I have been working on but I don't get the right answer. After drawing the Lewis dot structure of HOClO2, pick the incorrect statement of the following. A. The oxygen bonded to the hydrogen has two lone pairs B. the oxygens not bonded to hydrogen have three lone...
  16. N

    What is the format for ionic lewis structure w/ resonance?

    Homework Statement I need to draw NH4NO2 which is an ionic compound. 3. The Attempt at a Solution NH4 is fairly straightforward to draw, with one N in the middle and four H surrounding, and no lone pairs. The problem comes with NO2- which is one nitrogen bonded to two oxygens. However, one...
  17. A

    Sulfur Dioxide (SO2) Lewis Structure

    Hi, I drew the lewis structure of SO2. The one with 0 formal charges gives me two double bonds. But, I see on the web that one single bond and another double bond is an acceptable resonance structure. What do they mean? Sulfur can expand its octet. Having 0 formal charge is much more...
  18. Q

    N2O5 Lewis Structure and Bond Angle Analysis | 40 Valence Electrons

    Homework Statement Draw the best LS for N2O5, which studies show a) has a N-O-N central atom skeleton and b) Has a central atom bond angle of 180 degrees. Comment on the unexpected bond angle of 180 degrees around the central atom. Homework Equations There are 40 valence electrons...
  19. Q

    Lewis Structure; Non-bonding pair missing

    Homework Statement http://i.minus.com/jxoYt94CAd9LY.png Homework Equations The total number of valence electrons in SOCl2 is 6 + 6 + 7(2) or 26 valence electrons. Dividing by 8, this implies a total of three bonds formed with the central atom (the least electronegative atom, or...
  20. J

    How Do I Complete This Lewis Structure?

    Homework Statement Draw the best Lewis Dot Structures the following species: ClF4+Homework Equations none The Attempt at a Solution I calculated that there should be a total of 34 e- in the Lewis structure": 7 (1 chlorine atom) + 28 ( 7 from each of the four fluorine atoms) - 1(b/c the atom...
  21. T

    How to draw Lewis structure of molecules with N

    Many times, I find it hard to draw correct Lewis structure of molecules with nitrogen. For instance: the Lewis structure of H2CNN. I thought it should be double bond between C and N and single bond between N and N, like this: But actually it's not. I have done many problems like this wrong...
  22. Telemachus

    Understanding the Lewis Structure for NSF: N≡S-F and Formal Charges Explained

    Hi there. I have to determine the Lewis structure for NSF. So first I thought of something like this: N=S-F, with the nitrogen with four free electrons, the sulfur with two, and the fluorine with six. The formal charges gives -1 for Nitrogen, +1 For sulfur, and 0 for Fluorine. But the...
  23. B

    Lewis structure for Nitrogen Dioxide

    I am pondering on what the correct Lewis structure(s) for Nitrogen Dioxide (NO2) may be... I have come up with 7 possible structures, but am unsure which are correct and which are not. I have compiled a small list of notes for your convenience and they are all in this picture. Which...
  24. J

    Why Does ClNO2 Have Only One Double Bond in Its Lewis Structure?

    Homework Statement Draw the lewis structure for ClNO2 The Attempt at a Solution When I first drew this I had two double bonds in between the N and the Os. However, the answer suggests only one is a double bond in the structure. Why is this correct? Aren't we suppose to balance the...
  25. P

    What is the bond order of NO-, NO, and NO+?

    Homework Statement Bond Order of NO- Bond Order of NO Bond Order of NO+ Homework Equations No Equations The Attempt at a Solution I determined the Bond order of NO+ to be 3 due to their triple bond and the Bond order of NO- to be 1 due to their single bond Lewis Structures...
  26. QuarkCharmer

    Why do some Lewis structures have exceptions?

    Homework Statement ICl_4^- Homework Equations n/a The Attempt at a Solution I has 7 valence, Cl has 7*4. Ideally, they would be 8 and 8*4, and so. (40-35+1)/2 = 2 bonds. //the +1 is from the negative charge of the ion There are simply not enough bonds to go around, so when...
  27. P

    Why is Lewis Structure A Better for Diazomethane?

    Homework Statement I was taking a practice exam, and it asked for the "acceptable lewis structure for Diazomethane" I had narrowed it down to two possible results but can't for the life of me figure out why one is more acceptable than the other. I attached a picture of the two choices...
  28. O

    I was asked to draw the Lewis structure of NO2-

    i was asked to draw the Lewis structure of NO2-, and to write the formal charge of any atoms. so in the picture you can see my tried (the red number is the formal charge). now i also asked to decide what is the angle ONO. what i know is the shape of this molecule is Bent so the angle will...
  29. O

    Checking Lewis Structure of Barium Peroxide

    tell me if i correct i tried to draw the Lewis structure of what i think is Barium peroxide in the picture you can see the formula. in red dot is the extra electron. thanks.
  30. M

    Chemistry - Lewis Structure question

    I understand the idea of the Lewis Structure and the octet rule. What I don't know is where to place the atoms. And unfortunately my book doesn't explain it. They just draw the lewis structur and expect us to understand how they did it. For example: Draw the lewis structure of H_2CO...
  31. I

    Predicting molecular shape without drawing lewis structure

    Is their a method for predicting the molecular shape of molecules without drawing the Lewis structure? I am preparing for an ACS exam and would like to try to save some time on these problems. I think I could determine the steric number by counting the total electrons available, and...
  32. E

    Lewis structure, hybridization and VSEPR

    Homework Statement Consider the related molecules POF2- and POF3. Choose all the following statements that are correct for both molecules. Homework Equations A) P atom is sp3-hybridised B) The F-P-F bond angle will be approximately 109.5 degrees C) Geometry around he P centre is...
  33. B

    A question in Lewis structure?

    a question in Lewis structure? I know that Lewis structure is so easy to discuss ..but I have this compound : SnCl2 when I drew the Lewis structure of its , I had to make Double bond between the Cl & Sn ..but a teacher told me once that when the Cl is not the central atom it can just make...
  34. M

    Thank you!Lewis Structure Problems

    Lewis structure (Related! - Please Help!) I have 2 problems, please help me!please! thank you so much! Homework Statement Can you tell me if I am correct?Thank you so much!I tried acd and ac but it's wrong! :( 1. Which of the following are true about the correct Lewis structure of the SeF2...
  35. P

    Lewis Structure: SOCl2 Solution

    Homework Statement write lewis structure for SOCl2. Homework Equations The Attempt at a Solution .. .. .. :Cl-S-Cl: .. | .. :O: .. what i did was put S in the middle with a single bond on both side for Cl, each Cl has six dot. S has two at the top. I...
  36. D

    Finding the Right Lewis Structure: Formal Charge

    with lewis structures, if i come to 2 separate structures that both seem right, and i want to know which is right, and i check the formal charge, and get: for one diagram 0:1:-1:1:1 and for the other 0:0:0:0:2 which is better, i guess what I am trying to ask is, is it preferable to...
  37. D

    What is the lewis structure for IO3

    what does the lewis structure of (IO3) look like??
  38. D

    What is the best way to draw Lewis structures for transition metals?

    if i am told to draw a lewis diagram for PCl^{+}_{4} does this mean a melocule of 1P atom and 4 Cl atoms, the whole molecule with a charge of +1 or is it 1 P atom and 4 Cl^{+} ions, giving the molecule a charge of +4 what does the lewis structure look like, is it P in the middle with Cl...
  39. V

    Possible Error in Chloric Acid's Lewis Structure

    Hello everyone: I was looking at Wikipedia's page on chloric acid (http://en.wikipedia.org/wiki/Chloric_acid) and was wondering if the Lewis diagram there is correct. I will not link directly to it as it has a high resolution. It shows Cl with a lone pair of electrons having double bonds with...
  40. D

    Chemistry Lewis Structure of These Molecules?

    I need to write the lewis structures of two ionic compounds. Can anyone help me out? Thank you. 1) (NH4)2SO3 2) LiBH4
  41. U

    IF3 Lewis Structure Guide: Mastering the Bonding Pairs & Electron Counting

    Trying to draw Lewis structure for IF3. There's four atoms, so 32 electrons needed minus the 28 availabe (7 valence each) give 4 electron bonded pairs, which is 2 bonds... but there has to be at least 3. I'm stupid, what am I missing? edit: never mind i got it
  42. R

    Lewis Structure Help: CH3NCO Bonding Scheme

    i am attempting to figure out the lewis structure/ bonding scheme for CH3NCO. so far i have: O=C=C-N-H l l H H the Hs are attached to the second C then the N the formal charges seem to be ok i have a formal charge of 0 for O...
  43. J

    Lewis structure- and bases check please

    Could you check these? Which one of the following ions or molecules can act as a base? H2S NH4 ALH3 CH3 NH2 I chose H2S. Is this correct? Also I had to weire a resonable lewis structure for the molecule that has the following skeletal structure: O2NONO2 I wrote...
  44. P

    Draw the Lewis structure of oxalic acid (H2C2O4)

    There are many different types of kidney stones, but the most common is calcium oxalate, CaC2O4. The pH range of blood is 7.2-7.3. The pH of urine ranges from 4 to 8. Draw the Lewis structure of oxalic acid (H2C2O4) and the oxalate anion (C2O4-2). H2C2O4 Ka1 = 5.6×10-2, Ka2=5.42×10-5...
  45. W

    Lewis Structure + Molecular shapes

    3. Which of the following is the molecular shape of the ion, ICl4-? A. Tetrahedral B. See saw C. Square planar D. Square pyramidal E. Trigonal pyramidal I drew the lewis structure, 4 chlorines bound to an Iodine. Iodine has 7, Each clorine has 7 with 35 total, the bonds...
  46. R

    Lewis Structure Problem, Atoms of more than 8 valence electrons?

    I am confused. Doing Lewis structures is like balancing an equation, putting it together till all the valence electrons work with each other, as far as I can tell. :tongue2: However, some atoms have A TON of valence electrons, like gold which has 25, um, how would I connect it to other...