Lewis Diagrams Made Easy: How to Draw Lewis Dot Structures

Lewis Diagrams Made Easy: How to Draw Lewis Dot Structures

Welcome to Lewis Diagrams Made Easy with Ketzbook Today we are going to learn how to draw Lewis Diagrams for atoms and simple molecules, but before we begin, let’s start with a question. How many valence electrons does chlorine have? In order to answer that question, we need
to look at the Periodic Table. Remember that within any given column, all the elements have the same number of valence electrons. To get that number, all we do is count the
columns starting from the left. Skip the transition metals, and remember that the only exception to this is helium, which has only 2 valence electrons, not 8. Now, find chlorine in the Periodic Table. Remember that it’s symbol is Cl. See it in the 7th column? That tells us that it has 7 valence electrons. Knowing the number of valence electrons an element has is critical, and in Lewis diagrams, we use dots to represent valence electrons. So, the Lewis diagram of chlorine is the symbol Cl with 7 dots around it. When you draw the dots, don’t just put them anywhere. Instead, imagine a square around the element’s symbol. The dots should be neatly drawn on the four
sides of the square with no more than two dots on any side. Practice drawing the Lewis diagrams of a few
elements just to make sure you’ve got it. This is the Lewis diagram of hydrogen, which
has only one valence electron. This is carbon, which has four valence electrons,
and this is oxygen, which has 6 valence electrons. Where you put the dots doesn’t really matter
as long as you neatly draw them along the sides of an imaginary square and never put
more than two dots on one side. Lewis diagrams are often used to represent
covalent bonding in molecules and ions. In covalent bonding, atoms share valence electrons
in order to get a full octet or duet, that is every non-metal element wants 8 valence
electrons, except for hydrogen, which only wants two valence electrons. The simplest molecule possible is that of
hydrogen, H2. A hydrogen atom has one valence electron,
but it wants to have two. So, in order to satisfy its desire for another
electron, two hydrogen atoms will share their electrons with each other. And the crazy thing is that in the wonderful
world of atoms, the shared electrons are counted as owned by both atoms. That means that both hydrogen atoms are happy
because they both satisfy the octet rule. Now, we normally draw hydrogen and other molecules
like this with lines to represent shared electrons and dots only for non-bonding electrons. These two diagrams of a hydrogen molecule are equivalent because one line, which is a single bond, represents 2 shared electrons. In the same way, two lines between atoms would be a double bond and would be the sharing of 4 electrons. An example of a molecule with a double bond
is oxygen, which looks like this. Notice that in this Lewis diagram both oxygen
atoms have 8 valence electrons, 4 from the double bond and 4 from the lone pairs of electrons. By the way, 2 dots together are called a lone
pair of electrons. Some molecules contain triple bonds, which
we write using 3 lines that represent the sharing of 6 electrons. An example of a molecule with a triple bond
is nitrogen, which looks like this. Once again, notice that both nitrogen atoms
have 8 valence electrons, 6 from the triple bond and 2 from the lone pairs of electrons. Okay, how do you actually draw the Lewis diagram
of a molecule? Let’s start with water, H2O. There are 5 important steps that you need
to follow when drawing the Lewis diagram of a molecule. First, count all of the valence electrons
in the molecule. For water, each hydrogen has one electron
and we multiply that by two because there are two hydrogens in the molecule. The oxygen has 6 valence electrons. Add those all up, and we have a total of 8
valence electrons for the water molecule. Step 2, determine the central atom. The central atom is the one that all of the
other atoms will be bonded to. It is usually the element that there is only
one of. In the case of H2O, because there are 2 hydrogens
and only one oxygen, we choose oxygen as the central atom and write it in the middle. Step 3, draw single bonds to the central atom. Step 4, put all of the remaining valence electrons
on atoms as lone pairs. For H2O, we started with 8 valence electrons;
we have used four electrons for the two single bonds, so that leaves 4 more electrons left
over. We put all 4 of those remaining electrons
on oxygen instead of hydrogen because hydrogen is already happy with 2 valence electrons. Remember, never give hydrogen more than 2
valence electrons. Everyone else wants 8 electrons, but hydrogen
only wants 2. Step 5, turn lone pairs into double or triple
bonds to give every atom an octet or (duet for hydrogen). Pause the video and see if all the atoms in
our H2O are happy. Because each hydrogen has 2 electrons, and
the oxygen has 8 electrons, everyone is happy, and there is no need for double or triple
bonds, which means that our Lewis diagram of water is now complete. All right, let’s try one more example just
to make sure we’ve got this. Draw the Lewis diagram of sulfur trioxide. Once again, the first step is to count all
the valence electrons. There is one sulfur with six valence electrons,
and there are 3 oxygens with 6 valence electrons each. 6 times 3 gives us 18 valences electrons for
the 3 oxygens. The total would be 6 + 18, which equals 24
valence electrons. Step 2, determine the central atom. This time, sulfur is the central atom because
there is only one sulfur in the molecule. We write sulfur in the middle with the three
oxygen atoms all around it. Step 3, draw single bonds to the central atom. Step 4, we started with 24 valence electrons,
and we have used 6 electrons to make the 3 single bonds. This means that we have 24 minus 6 or 18 valence
electrons remaining. We now put those remaining 18 valence electrons
on atoms as lone pairs. Count by two’s when adding them. 2, 4, 6, 8, 10, 12, 14, 16, and 18. That’s it, we’ve now used up all of our
valence electrons. Step 5, first pause the video and check to
see if any atom does not have an octet or duet. That’s right, the sulfur is unhappy because
it only has 6 valence electrons. So, what can we do to make it happy? We cannot just give it more electrons, since
we don’t have any more. Instead, one of the oxygen atoms can take
one of its lone pairs and share those two electrons with sulfur in another bond. The double bond between oxygen and sulfur
now makes every atom happy with 8 valence electrons. Be sure to follow these steps when drawing
Lewis diagrams. Thanks for watching. Please comment, vote, subscribe, or check
me out at ketzbook.com.

Dereck Turner

100 thoughts on “Lewis Diagrams Made Easy: How to Draw Lewis Dot Structures

  1. Kowalski says:

    Finally the right fuckin video!!!!

  2. أ. آمال كيميا says:

    Please please tell me the name of writing programe؟؟؟

  3. Patrick Casta says:


  4. Grecia Perez says:

    wow i get it now

  5. Rigged World says:

    you sound like jonathan morrison

  6. Valeria T says:

    bless your heart

  7. John Ash says:

    i cant understand the sulfur trioxide

  8. Acheng Gamer says:

    thanks dude you just saved my grade

  9. tina editsscx says:

    I've learn a lot about this, Than to my professor! Thank you so much♥

  10. Paytm Guruji says:

    which application from u make video

  11. angelina guadalupe says:

    im still confused bruh

  12. H · 23 years ago · but actually says:

    1:53 who writes "H" like that?

    Edit: 3:10 once again "N"
    Edit: 5:49 "S"

  13. H · 23 years ago · but actually says:

    My teacher litteraly just did wrong…for example in the last part she did
    . .
    : O :
    . . | . .
    : O :- S -: O :
    . .
    Edit: i know your right but if i follow you….she gonna mark me wrong because she thinks shes right

  14. Anudeep Annangi says:

    This video helped me understand how to draw lewis diagrams the easy way. It became crystal clear! Thanks!!

  15. Deo Manuel says:

    That time when a random youtube channel teach you better than your chemistry teacher

  16. Madeline Castro says:

    so this means that in the end, the elements displayed have to form an octet and each valence electron has to be distributed with at least one electron on each side?


    Thank u so much

  18. Avinash Barbind says:


  19. John Tran says:

    I have Chem test in an hour thanks for help

  20. Elizabeth Eventing says:

    This… actually made sense. Thank you!

  21. von anthony macaraig says:

    i wish the teacher is online, instead teatching for an hour better to be 7mins and then done

  22. Aaron Romero says:


  23. Brandon Thai says:

    this dude got nice handwriting

  24. water melon says:

    Thank you so much. Im a first year student and it's difficult following what the lecturer is saying when you're about 200 in your class and you come in 2 minutes late…

  25. ilayda k says:

    I have trouble understanding this, i could draw the dots but i can't really understand whether the molecule is polar or a polar. Like H20 was drawn like it was polar.

  26. Amna Haq says:

    you’re amazing! please continue making more videos like these 🧡

  27. A420-360 says:

    They should have called covalent bonds Communism Bonds


    Is there any dative bond in NO2 molecule

  29. keira feng says:

    thank you for saving my life

  30. Gaurav Rajput says:

    too good sir i like plzz make more videos like this


    But doesn't that make the other 2 oxygens to have 7 valence electrons?

  32. Osama Momani says:

    very helpful, thank you

  33. Gowtham Ar says:

    school teachers should put their heads down….. best video

  34. RE loading says:

    this video is a godsend directly from heaven to me

  35. Evil Patrick says:

    This is my teachers whole day lesson in 7 mins

  36. xoxoali says:

    My highschool chem teacher refuses to reteach this because “we learned this in middle school” I’m sorry? that was 2-3 years ago :/

  37. Hemalatha Govindaraj says:

    The best video am completely satisfied

  38. A Magic Reader, Alex says:

    It's such a made video that I can understand this so easily!!!!!

  39. Adrian Monceau says:

    Omg THANK YOU so much now I actually understand did, whereas I was struggling for the past month.

  40. zyra caibs08 says:

    Thank you for this video. You're better explaining than my science teacher. No offense meant to my teacher tho

  41. Skyicee says:

    when your teacher doesn’t like to teach

  42. Doctor Gyadu says:


  43. i eat a33 says:

    Who is studying for a test?

  44. Bob Thebb-Illder says:

    This is easy WEAK SAUCE.

  45. Dasa Saren says:

    Can you show how to do. HCN

  46. LuciaBiggles says:

    wow i was so confused and you fixed it, thank you so much

  47. TECHNO IN FIELD says:

    Best video of this topic on YouTube. Thank you for this I am now understand my topic. Well done

  48. Glitch Gaming & Fun! says:

    all the oxygen atoms had 7 electrons with 1 bond making it 8. It means that there is 1 to many electrons on those oxygens. That makes them negative and your suppose to put a little negative symbol on those oxygen atoms and make an electron a star or if its not then you keep those electrons on the Sulfur with a half arrow to show migration.

  49. Margaret Diego says:

    Thank you!

  50. Ayman Said says:

    you are a good man

  51. ng nid says:

    Thanks for the explanation 👍🏻

  52. H3ROYT says:

    I have a test tommorow n i wanna say thank you for making this clear to me

  53. MLGen GT says:

    To the 515 people or more who disliked probably were too late to find this video and had given 8 valence electrons to Hydrogen ::DD

  54. Fake Nins says:

    Pls be my new teacher

  55. Megan Keating says:

    thank you this was really helpful (:

  56. Brooke Chapman says:

    when your chem teacher doesn’t teach and you turn to youtube videos for help

  57. سمر خالد عراقنة says:

    Thanks so much ❤❤

  58. EDIE DOWLING says:

    ur handriting is good

  59. Hevin Amber says:

    NICE review

  60. Tae Hyung Kim says:

    Việt Nam 💖💖💖💖💖

  61. qwertyuiopa.skdlw abdjj. says:

    Thanks this helped alot I never learned this kind of stuff in my school

  62. Miss Adorkable says:

    Formal charge was left off this video if your class requires them on the diagrams. SO3 did have charges.

  63. ChemZilla says:

    Hey, but sulfur trioxide has six valence electrons hence it makes makes 3 double bonds w/ oxygen on ur vid sulfur has only 4 valence electrons octet or dublet isn’t the most important rule and there’S huge amount of exceptions to this rule even on primary level.

  64. mikateko33 says:

    Wow.Well explained. Thanks

  65. Srivats Varadarajan says:

    You are a legend thanks so much

  66. suraj purohit says:

    Sir I Am from india…..best explanation ❤❤❤❤❤❤❤❤❤

  67. yk sj says:

    The last one can be drawn in 3 ways

  68. Red Pen says:

    amazing video! i didnt pay attention for 1 week. i just watched this video 2 hours before my test, practiced a couple, and got a 100! tyvm for this great video

  69. Life of Joy says:

    Its was awesome at last

  70. Slurp says:

    I have a science test today, thank you.

  71. Slurp says:

    I have a science test today, thank you.

  72. Jess Kray says:

    Thank you. I love you

  73. Delete it Fat says:

    thank you!!!!!

  74. zappy boi says:

    This was more helpful than the 30 minutes of my teachers complicated lesson

  75. Lol Pol says:

    I love this video
    Finally I got the right one 😭

  76. Miguel Ramirez says:

    Told you this would help @A

  77. Emily Tran says:

    im so happy im gonna cry

  78. William Gratchic says:

    Lack of detail as to "why".

  79. T Williams says:

    U are so much better than my professor

  80. Joey Marquez says:

    ketzbook, this has helped a lot

  81. C BAXTER says:


  82. hashem kingston says:


  83. Mohamad Al Halabi says:


  84. Gladwin says:

    This has been great help🔥

  85. blip trip says:

    So all the oxygen atoms are negative right?

  86. RicarCool 3886 X says:

    who heard the fard of the dude at the minute 4:26?

  87. Payton Tanner says:

    This video is being used as a torture device

  88. Tara Wilson says:

    Great video. Very clear explanation. You're a great teacher!

  89. LegitGamerXpro says:

    Is it me or does the hand have an uncanny valley type of feel

  90. rafal aziz says:

    Thank you so much its really helpful video

  91. Jeon Louise says:

    God bless youuu
    God bless you
    Continue to use the gift that God gave you
    Thank you so much!

  92. MADMICHAEL 15 says:

    This actually helped unlike my bumass chemistry teacher

  93. Hush says:

    It's satisfying to see the dots are perfectly placed there compared to the ones i draw on my paper

  94. Hawraa Msheik says:

    In carbon dioxide the number of valence electrons will be the same if it has triple bond on a side and single bond on the other one how do I know which is correct?

  95. neggit says:

    If it was up to me, you'd get my professors paycheck instead of her. Thank you

  96. carol phiri says:

    make more videos please 💓💓💞💜💖

  97. Rucking Fetard says:

    Hallelujah give this man a statue!

  98. Azzaey Luna says:

    Thank you

  99. kamusiime azaria says:

    Please SOME HELP,I got a little bit lost when it came to drawing COCL3,

  100. Lucas Godwin says:

    My chem prof should be ashamed that it was this easy to explain this and he couldn't

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