Bonding Models and Lewis Structures: Crash Course Chemistry #24 

Pssst... we made flashcards to help you review the content in this episode! Find them on the free Crash Course App! Download it here for Apple Devices: apple.co/3d4eyZo Download it here for Android Devices: bit.ly/2SrDulJ

when you are crying watching this the day you have your chemistry test (':

You guys did something that school failed to do... I learned something.

Please do a video on VSEPR theory

I know you guys get this very often, but thank you so much. Chemistry doesn't come naturally to me, and you guys present the information in such a simple and straightforward way. I've always thought learning was fun, but you guys make me enjoy even the hardest subjects (to me). Thank you for doing this!

I learn more in a ten minute youtube video than I do in an hour and a half of chemistry class..

I know half of you are here cause you guys have a final tom

"model students"......*gasp* so he knows that all the people watching his videos are stressed highschool students who are cramming for their tests the night before the test?!

Can you please do a Video on Vthe VSEPR Theory and Molecular Geometry

i love the way they also include the history of chemistry. it gives viewers a chance to go deep into the world of chemistry. by sparking curiosity. Very well done. inspiring

I agree with many people here. I've read chapters, studied slides from lecture, and completed the practice sheets and I would still get caught up on this simple subject. You guys simplified it to my full understand in just 8 minutes. Amazing!

Thank you for helping me try to pass my exam

When I get stuck with chemistry, I come here for a mental break and a different perspective on the topic at hand. Thanks for being so good at providing both!

THANK YOU! I was so lost, im not a chemist im a mom whos going back to school to get my bachelor's. I was scared I wasnt going to get it, and you really helped me so much... it finally makes sense

As a biochem major who's a little nervous about tutoring General Chemistry I next semester, I really appreciate this video (: great video layout, Hank -- thanks a lot!

"Doing whatever models do on saturday nights" AKA enough coke to kill a horse

You guys are the only reason why I'm passing chemistry, so I thank you.

I looked at this video and saw "Hank" in the description. I was like, Hank? Like Hank Green? Naw... Then OMG! Hank! Automatic attention getter: being taught chemistry by one of my favorite youtube vloggers. Thank you!

*flails hands* YOU SAVED ME FROM FIRST EXAMS WEEK FOR IN PREPARATION FOR HSPT! *praise hand flails* FOR THAT I PRAISE THOU

“There is no such thing as a quadruple covalent bond” *Transition metals would like to know ur location*

"All models are wrong, but some are useful." -George E. Box

It's hard to comprehend everything you are saying when you speak so fast. Not everybody is a natural with molecular geometry, chemical bonding and Lewis structures, so most of us who are learning appreciate when the information is slowed down. Thanks ^^

I'm learning this in 8th grade and my teacher literally taught it for 1 minute. Thanks, you're a better teacher than my science teacher.

0:50 - the universe is weird get it? cause hank wrote a song about why the universe is weird? I don't even know why that cracks me up

This is a must-have channel. Great job. Do you guys have a Physics crash course planned for the future by any chance? Does anyone know an equally comprehensive channel for Physics?

YOU ARE AN ANGEL. I HAVE A COLLEGE CHEMISTRY TEST IN TWO DAYS AND THIS IS HOW IM STUDYING THANK YOUUUUUUUUUUUU

screaming right now.... less then 2 days before AP chemistry exams ;-; funny thing is in my AP chem class when drawing Lewis structures we use lines to represent bonds. but apparently we found out the AP exam says those lines are 'too advanced' and will receive ZERO credit if you have lines in the drawing of Lewis structures

4 years later and these are still helping people. Thank you so much

Thank you CrashCourse!! You guys are literally saving me in my online chemistry class. I really appreciate all that you do to create such amazing and straight-forward videos.

I have a test in two days and I'm an ADHD student seated in the back of my class and all i have to say is *chef kiss*

"It's important to realize that all models are imperfect to some extent"- that's deep

8:48 Oh baby a triple!

Hank, and all of the crash course team, you guy are like legit, the best. I praise you for doing this for free on youtube.

If you think that this show teaches you what school doesnt, you're wrong. All these topics should be covered in highschool. This is simply a briefing. Do not learn your highschool curriculum from this channel, please, learn it in highschool, however, this is still useful as study and review.

literally cramming 3 hours before my finals exam

We are all model students? DOES THAT MEAN WE ARE NOT 100 percent accurate? :O

The comparison between fashion models and scientific models was really good and helped me view models (both types) in a different perspective

I must say that u make chemistry look and easy. your videos are helping me a lot

Thank you so much, Hank! These videos never let me down. I can totally count on CrashCourse when I need some Chem help. You explain things so clearly!

I am in a desprate need to someone like him to be with me in every lecture in every subject.

We often watch crash course videos because it's short to watch!

Hey theres something that confuses me. Why is H2O bent instead of linear? Should the H have bonds and the 4 dots of electrons be on the top and bottom of oxygen?

Myself 16 years old:- what do I prefer to learn, English or Chemistry? English so I can talk with people around the world! 18 year later... Using English to learn chemistry for a bachelor's degree I need to start a business I love XD

I still dont understand how do I know for sure when the atom form a single double or Triple covalent?

I owe this guy a life debt. I have a chem exam tomorrow and he's saving my life (did the same fro bio last year)

*1:45** I throw my models of atoms in the air sometimes saying aeeeeeh ooooohh gotta let goooo.*

I don't know what I'd do without this. My Chemistry book told me to write Lewis Structures, and I didn't even know what they were.Thank you Hank.

Hank Green, I cannot thank you enough for this video.

I'M A FRESHMAN IN HIGH SCHOOL DOING COLLEGE LEVEL CHEM. I HAVE NO IDEA WHAT I'M DOING. GOD BLESS THIS VIDEO.

Thank you for the explanation. It was great. You need to get your eyeglasses adjusted. You repositioned them 7 times during the course of your discussion. May have been 8 actually.

This is the first NOT-BORING Chemistry discussion I have ever seen in my entire life!

9:00 My PhD in Google tells me you're wrong

This show has saved my life too many times to count.

"model students" (awkward sarcastic face) lol 10:50

Is it weird to watch these for fun...

When your teacher doesn't give a damn so you have to watch RU-vid

thank you, 2013 hank, for finally letting me understand lewis dot structures! my test is in a few hours, ahhhh

I don't think laughing like this because of that last joke is healthy...

I would love to have a link in the description that tells where Hank gets his t-shirts! I especially like this one!

don't blink, you'll miss the whole video

You guys were really helpful, considering i went from 40% in september to 65% in November 11th grade, and all of a sudden i have a weird feeling of buying my own very little Trebuchet

This guy is replacing bill nye

a tip for finding out covalent bonds: 1. add valence electrons, 2. if the atoms were noble gases, add the electrons they would have eg H-2 F- 8, 3. subtract the noble e's from the valence ones and divide by two. This makes sense because the noble electrons are the ones you don't have (so you must share) and each bond has two.

Hank needs to stop wearing awesome shirts so I can keep my mind on chemistry instead of, "Where do I get that awesome shirt??"..

This video is magnificent! I have learned more from you in 11:38 than I have from my teacher in the past two weeks. Thank you!

Chemistry is the best part of science!!

CrashCourse is wonderful especially as a supplement to my irl chemistry class because it simplifies the information load without losing anything important or sacrificing the ease with which the viewer is able to understand it. Clears up so many things my teacher glosses over!! Thank you!

If only you taught at my school

I was a bit disappointed to see that there was not any whole video elucidating the exceptions to the Octet rule, or the concept of "half bonds" (such as in benzene, with a six-carbon ring of "one-and-a-half" bonds). Aside from that, I appreciated the video.

Aw, I wanted Brazilian models :(

Hey guys! Listen up! Here's some shortcuts to building Lewis Structures or Skeletal Structures (those are more Organic Chemistry...they are the ones that look like lines and pentagons and hexagons). Assuming all atoms are neutral, Carbon will always have four bonds, Nitrogen will have a single lone pair the three bons, Oxygen will have two and two, and halogens (F, Cl, Br, I & At...not that you'll ever see At) will have a single bond and three lone pairs as they are more electronegative and thus rather grabby with electrons. Now, if there are formal charges, which are basically like charges in general but internalized inside the molecule, that changes things, but not too much. Positive formal charges makes Carbon act like Boron with three bonds and that's all. Nitrogen will act like Carbon with three bonds and no LPs, Oxygen will have Nitrogen's bond configuration with three bonds and one LP, like in the Hydronium ion. Halogens will be two and two. That's all for positive formal charges. Negative formal charges move things in the opposite direction. BTW, it helps to visualize this on a table. Perhaps when/if any of you take Organic Chemistry your textbook will have such a table. Anyways, negative Carbon will have Nitrogen's bond config with three bonds and a lone pair. Nitrogen will be like a neutral Oxygen, Oxygen will be like a halogen with a single bond and three LPs, and if a halogen has a negative formal charge, then you have an ion, and thus a net charge as well. Hopefully this will help you guys. Two LONG semesters of Organic Chemistry...not once did I need to tally electrons when building Lewis/Skeletal Structures.

only 5 min in did he start actually talking about them wtf

You did better than my professor in just a few minutes. THANK YOU!!!!

I love these vids

this is really helping me study. i have exams coming up and these videos are the only way to keep me interested, and i love the little random facts that I find so interesting that i haft to think about them more.

Make a physics crashcourse

@0:53...."the universe is weird" holly god...his expression...luv that xP

Wow . you talk sooo fast . I had to pause to understand some of it . 😅 Thanks for sharing !

Next week's orbitals episode will (probably) start to help you understand that. Don't worry, you're not missing something he already explained.

Where'd he get that shirt

you are my hero. I have a chemistry test tomorrow and I finally understand !!

Why don't quadruple bands exist? Why can;t there be a quadruple bond of carbon? C2

Hank Green, ladies and gentlemen, always saving my notes from complete anihilation. Seriously, man, you did the impossible: YOU MADE ME UNDERSTAND CHEMISTRY!

Lol he talks really fast

So glad you make these videos as my chemistry teacher is a shocker! Oh hank you say the sweetest things ;)

great teaching . but you can you please talk little slower

I wish my chem teacher this year told me about these videos, my APUSH teacher showed us this stuff as a reinforcement to stuff we already knew. Didn't know that in 2 chem videos I would finally get what my chem teacher would speed through the year and ignore everyone and do something on the computer or play with her phone in about 20 minutes thanks.

Can you be my teacher?

"What's eating Gilbert Lewis?" lol nice one, Crash Course

I'll be honest I don't feel like this fast talking zip through crash course if of any help at all. There's tons of other videos where they will explain it slowly and carefully, step by step. I can't keep up with this motormouth, he whizzes through topics as if he were explaining something that we already have a working knowledge of.

>Saw this during a Science lesson >Switched to Personal Account >Subbed I like how this information is delivered! Keep it up!

I'm a model and I find this offensive.

You guys are amazing. I would have failed so many exams if it wasn't for CrashCourse.

2019?

8:59 Oh yeah! Quadrople Covalent bonds bois!

you talk very, very fast.

FANTASTIC! I watch it at 75% speed, and some times at even 50%...., and super speed problem is solved☺️👌 (thanks from Spain!)

Omg I wish you wouldn't speak soooo fast!!!

All I can say is ....... Thank you to people who work at crash course.