Redox Reactions: Crash Course Chemistry #10

All the magic that we know is in the transfer of electrons. Reduction (gaining electrons) and oxidation (the loss of electrons) combine to form Redox chemistry, which contains the majority of chemical reactions. As electrons jump from atom to atom, they carry energy with them, and that transfer of energy is what makes all life on Earth possible.
Watch this video in Spanish on our Crash Course en Español channel! • Reacciones Rédox: Cras...
Thank you to the following chemistry teachers for their assistance:
James Sarbinoff
Rachel Wentz
Edi González
Lucas Moore
Chris Conley
Addie Clark
Julia Rosinski
Special Thanks to Matt Young at the University of Montana (Geosciences Department, Environmental Biogeochemistry Lab) who helped with the chemical demonstrations.
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
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[@crashcourse]

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

[@lereverse1998]

Stfu

[@Inbbnbb]

Ok hank and co

[@trevorlei4096]

@@lereverse1998 chill out chelly

[@lereverse1998]

@@trevorlei4096 haha

[@meganpennington343]

Funny story about redox reactions. Did you know that combining Hydrocloric acid and CuSO4 makes chlorine gas? Did you also know that accidentally creating chlorine gas on your first day of grade 11 chemistry puts you on your teacher's watch list for the rest of the semester? I didn't know that before, but I sure do now.

[@tensequel7818]

lol did anyone die

[@andrewminczeski8528]

As a chemistry teacher, why did your chemistry teacher give you hydrochloric acid on your first day of chemistry?

[@loganscully373]

@@andrewminczeski8528 its just hydrochloric acid, I've been getting it since I was like 12

[@nathanyein]

@@loganscully373that's sarcasm right?

[@loganscully373]

Nathan Yein nope

[@RhyminCarly]

As it is now 1:30 AM, I have a chemistry final exam in about six hours. Thank you, Hank, for being a fantastic teacher. However, redox makes me feel rather ill... For most of the video I was like, "Okay, yeah, that makes total sense! I can DO this!" and then chemistry decided to do what chemistry does and become exponentially more difficult just when you think you've solved it.

[@ohheycrystalhey]

Hank noooo you're making the same mistake that my math teacher makes. When you say chemical equations, please write them down or have them floating in the air above your head or have them somewhere that we can see! If you say "ammonia plus acetylaldehyde forms blah blah" it makes perfect sense in your brain, but it's difficult for me to focus on and understand the components of the equation unless I can see them. Please keep the equation visible as much as possible! It would help a lot!

[@nnaeem10]

Turn on CC

[@blackphoenix251]

did this lesson become useful to you after 5 years?

[@nicholasdsilva1832]

amen

[@carrie-annethomas2778]

@Goncalo Oliveira Since there's almost 400 likes on that comment, I'm gonna guess she's not the only one. xP

[@disconsolate3235]

@Goncalo Oliveira why would they bother commenting when liking the comment means they agree with it already?

[@TheNextNotch]

I don't know who this guy is, but I will find him and i will hug him.

[@kobewankenobi8926]

His name is Hank Green

[@leodaza3]

if you like this, you'll like his other channels too! :P

[@wewemcrhyne]

I think he’s saying “who’s Hank?” As is asked on all of John Green Vlogbrother videos!!!

[@lereverse1998]

I'm writing this comment so u try and remember when u wrote this and how uve changed

[@TheNextNotch]

@@lereverse1998 I'd still hug him

[@alanamesko8717]

you can also think of reduction as the reduction of CHARGE that occurs when an atom gains electrons. When an atom starts with a charge of 0 but gains an electron, its overall charge is REDUCED to -1

[@GamePhysics]

Yeah... I'm failing this exam. Thanks for telling me, crash course.

[@samymucho5494]

Same...

[@GamePhysics]

samy mucho I passed! :D

[@BlackIsOut]

lol

[@roooose16]

+GamePhysics wow, so much for that.

[@imamongthem3422]

i failed

[@Rin-qj7zt]

reduction is totally a name that makes sense. if you gain electrons, the charge has been reduced....

[@22Tech]

+Wulframm Rolf thanks fam

[@jasonslade6259]

+Wulframm Rolf Only because somebody arbitrarily decided that Electrons would be negative and protons positive. So I guess it works out by complete chance.

[@Rin-qj7zt]

Jason Slade that's my point tho. it was supposed to be slightly humorous. twas poorly written tho

[@zead9481]

it is really confusing for us new learners so yeah.

[@sxge4751]

I’m a new learner, you opened up my eyes

[@crazydang101]

I'd just like to thank John and Hank Green for making these amazing Crash Course videos that have taught me so much about the way the world works. I'm 15, and I love to learn, but unfortunately my teachers don't think I'm smart enough to take chemistry until I'm a senior. I love school. I love learning. I love writing. I'm introverted and a geek. I hope to someday be a Therapist or a writer. I just want to thanks thank you so much for making these videos. :) It means a lot to me.

[@mariahmolina2527]

All I hear is blah blah blah electrons blah blah 😩 definitely failing this test 😭

[@mathewmjohn7322]

mariah molina Check out Exam Fear.

[@mathewmjohn7322]

Krishna Narayanan Yeah! And you?

[@PrincessTanyaBarbie]

+Krishna Narayanan Indians unite xD

[@mathewmjohn7322]

Krishna Narayanan Wow, its astonishing to know that you are a girl! No offence, I mean no one could never decipher it through your name.

[@mathewmjohn7322]

Krishna Narayanan And yeah, John and Mathew are common names among Malayalees or Malayalis , whatever.

[@SophiaSu52]

You can also think of it as LEO the lion saying "GER" (grrrr). Losing Electrons Oxidation Gaining Electrons Reduction

[@coolbeatguy]

Thx I really needed that!

[@chancepark6253]

also reduction REDUCES charge

[@xAneesaxful]

We use OIL RIG in Scotland haha : Oxidation is Loss Reduction is Gain.

[@najeebal-shabibi9394]

Aneesa A also in Britain, I guess the education is very similar

[@danishstrikes]

Najeeb al-shabibi I live in texas and we also do OIL RIG :D

[@haditmarquez4940]

"AnD tHoSe ArE aLl ThE rUlEs" sir i need to remember all of these by tomorrow!! }:(

[@maliciousmarka]

Quick note: whenever you (yes you) hear about redox, know that reduction and oxidation is occurring (as the name says 'Red' for reduction and 'Ox' for oxidation). When you finish a redox equation, if an element or molecules redox value is going down from the reactant to product side, it is being reduced (but remember scientists are odd which means it's gaining electrons) and when it's redox value is going up, it's being oxidised (meaning that it's lost electrons)! I hope this helps.

[@LoLIHateMyNameLoL]

Let's all just give up to life and become non-productive members of society.

[@jairustheadventurer3935]

Z Adel NO ☭!

[@jetkwan2935]

Let's just kill ourselves so we don't become a burden to society

[@shaimamiah]

i agree

[@toshido_yamada]

good bye cruel world

[@nikkilabuckauful]

There is an error at 7:49: They write N2 + 3e- = 2NH3, it is not balanced as there are no H on the left, there are 3 negative charges on the left and no charges on the right and there are 2N gaining each 3e- so in total N2 is gaining 6e-, The correct half-equation is N2 + 6e- + 6H+ ---> 2NH3. Also the second half equation at 7:55 is wrong: the correct one is: 3H2 --> 6H+ + 6e-. Adding their two half reactions: N2 + 3e- = 2NH3 and 3H2 --> 2NH3 + 3e- would give me an overall reaction: N2 + 3H2 --> 4NH3 which is wrong.

[@daetsmlolliw]

The electrons are from The hydrogen

[@InnerSunshine]

It's not too "fast" it's designed to be rewind and re-watched as you need to. My notes from this video: History of "Reduce" comes from metals being heated-smelted and they got lighter: "reduced". O2 was leaving the metals making them lighter. Today we think about it as electron transfer. O2 is the best oxidizer, pulls electrons off other things "electronation and de-electronaiton" is maybe worse than "redox" oil-rig = oil oxidation is loss of electrons rig reduction is gain of electrons When your cells convert sugars into energy, for thinking and movement, that's redox. Plants doing photosynthesis, that's redoc. Batteries, is redox, fire is redox Modern chemistry keeps track of the electrons. The movement of electrons is the "currency" of chemistry, especially redo0x, who is ahead in electrons, who is behind or losing electrons. Forming of compound molecules is like a marriage. When the bonds on a compound break, who gets the electrons is of interest.

[@ronschlatter822]

If I'm following what you are saying, the slide Reduction Half Reaction at 9:36 should show the +1 above the Ag in the compound rather than above the Ag on the product side of the reaction, where it is elemental and has an oxidation # of zero. Love your work.

[@ZiggyGreen123]

How can you hate on whoever named these reactions. In reduction, the oxidation state is REDUCED by the gain of electrons. It makes complete sense.

[@FastestCrafter]

Crash course; bashing trump since 2013

[@aasthasharma3820]

Haha

[@DudeWhoSaysDeez]

heh

[@SS-hv5sy]

i thought they showing that he is a rich guy

[@kateorourke6064]

M1FF3D we stan

[@benjiwyatt8812]

Graig Simmonette- If you think people who knew Trump actually liked him until he ran, you weren't paying attention. Saying he's not significantly different from other presidents is insanely naive.

[@InterrobangActivate]

Thanks really helpful, I never really got this in class. I do feel that Crash course could do with some examples or questions. :)

[@catalyst-sai5180]

I am class 11 and it is 10pm having exam tmrw at 8am thanks i feel i understood but still fell empty thanks i understood something good than wasting

[@zippyman28]

Simple yet thorough.

[@XaurielZ]

It made my Canadian soul unreasonably happy to see a loonie being used as your example of a "dollar".

[@juliapelech4094]

this man has single handedly saved my grade in so many different classes over the years i cannot thank you enough hank

[@lynxdre]

How many people here are rushing for a basic lesson before their exam haha because I am and honestly this video is not as helpful as I hoped it would be :( which I understand because he's just trying to make the topic interesting with fun facts when what I actually need is a actual school lesson... instead of surfing around the Internet

[@krlormand2724]

+Lynxlynxlynx Jay Try Khan Academy. They do an excellent job of going more in-depth and also showing example problems.

[@davidbliss8352]

+KR Lormand, Thank you. This tip was extremely helpful.

[@charlottekraft2657]

Haha this sums up my situation lol

[@kumarichhetri7982]

Same here😣

[@div_yam2304]

This is a CRASH COURSE dude, its meant to be studied much before the exam.

[@rogerdotlee]

I've always had problems with Redox reactions. I still do. This is helping, I can assure you, but I'm still more than a little confused. Ah well, I'll watch it again a few times and the answers will shake out. They always do.

[@NeonsStyleHD]

Go over to Khan Academy and watch their videos on it. You'll get lots of examples, and it will be explained fully and you will definitely understand it after watching it. Google Khan Academy, click Start and start learning for free. There's even worksheets if u really want to make sure you understand it.

[@rogerdotlee]

I've been to khan academy. It really helped with my studies of Calculus. I don't know why I didn't think of it myself.

[@Lainelainehere]

I think it is pretty normal o.o

[@joshsoolee]

is that Donald Trump swimming in a pile of gold coins at the start?

[@Jumpingoutoftrees]

First one I've watched that I felt like I really didn't follow what happened and I'm not so sure I would even with watching it a second time. But I"m sure this would be an awesome refresher for someone who had already learned this before.

[@jordanorsak938]

I used to watch this in high school chemistry (because my teacher didn't write any lesson plans). 8 years later, watching this because chemistry is mega important. Thank you CrashCourse

[@hicketre2006]

Thanks Hank! Love your videos. You've saved me many times. To everyone else complaining about his speed: There is a LOT to understand here. If you need to 'get it', then pause the video, analyze the curriculum and do the work. That's the only way you'll get good at something.

[@meltdown6856]

Here’s a good way of remembering why reduction is called “reduction”. Electrons are negatively charged, so a “gain” in electron caused a “reduction” in charge. Like if Sodium cation (+1) charge recieves an electron, it become Na(0 charge), so it’s charge reduces

[@rockingupthewrongtre]

Hi CrashCourse team: I have an idea. I've been following your videos for the past year or so and it's changed my perpective on how i viewed my high school years. I wish I had the focus that I have now, unfortunately those years are way behind me. Thinking back on my lack of focus, I feel like much of it was due to the fact that I had no way of relating the information in chemistry, physics and pre calculus to what i thought would be real life after high school. Having much more experience now

[@peteriyida4485]

Bro, your videos are rad and your community crash course is a beast

[@amandawilliams7488]

You're fantastic. If you were a professor at my college, i'd take your class in a heart beat.

[@roselydonald3142]

I fucking hate that I have to know this shit for school. I'm not gonna be a scientist. Fuck.

[@ElliotLowell]

Rosely Donald The point of learning it is to have general knowledge on the subject and to give you a taste of it in case you might actually like it. Most often times someone can hate a subject but end up loving it after taking a course on it. You know the whole, "I thought I hated broccoli until I tasted it" charade. And if you hate chemistry, you know you aren't going for it in college so it helps taking the course to discover what you want in your life. Personally, I love chemistry.

[@roselydonald3142]

superkakashifangirl This is not "general knowledge" and what you like in school usually depends on what teachers you have. I've hated chemistry since the fucking beginning.

[@ElliotLowell]

Rosely Donald It is indeed general knowledge. The reason for this is because the entire world runs with chemistry, biology, math, and physics. It's general knowledge to understand the things in your life, every other student and students before you have learned it. How your shampoo is chemistry, breathing is chemistry and biology. Physics is your sun, house, and pretty much everything in your view. To take highschool classes of these subjects just touches the surface of what each thing is and understanding the bare basics of how it words and how you manipulate your world with it. Sure, someone can live without it, but the entire subject is just general knowledge. It doesn't even push into the scientific data and explanations, it just shows you that your world is made of all of these. It's 'general knowledge'. As for teachers, I never had any. With homeschooling and now online classes I've been my own teacher and I pretty much love every subject (except math, math is scary). I think maybe you're basing it on a teacher you didn't like, and I think that's ruining what fun you could have with the course. And even then, if you still hate it, I understand. I don't like math but there are still the occasionally fun things going on in there, like Sudoku.

[@roselydonald3142]

superkakashifangirl You obviously don't know what general knowledge means. General knowledge includes things that either most people know or what you need to know to function and remain active in your life. WTF, I don't need to know chemistry to know how shampoo works. How does that even relate to anything? You're logic with relating subjects we have to learn to real life is faulty. In no situation am I ever going to have to use algebra 2 (in a game or real life).

[@nathanielsandosam1]

Rosely Donald Just leave than stop complaining it is general knowledge for those who need to or want to do the chemistry course this is so basic compared to the rest of chemistry

[@kuhhchow]

Leora = Lose Electron Oxidation Reducing-Agent Geroa = Gain Electron Reduction Oxidizing-Agent *thumbs up :)

[@johnhilbert7640]

Ok I give up. Chemistry is just too complicated. I'm coming back to math.

[@joshuawalker5825]

It is never too complicated if you work at it at your own pace. It is just a subject you need to get familiar with :)

[@deathstroke7722]

Yes but sometimes you can't learn it at your own pace cuz your professor thinks it hilarious to rush through it and explain very little

[@williamloo2265]

aaaaaand this is why I wonder why I even bothered to take summer chemistry.

[@alexpeterson3200]

Come on, he said it right there, its 3rd grade algebra. Nothing like trying to apply multivariable vector calculus to non-euclidean relativistic space like what we all did in 6th grade, right? :P

[@JoeSmith-bt7wi]

i know how you feel. i have to watch these videos several times; I'll often replay the same two minutes over and over.

[@chocolatedream0612]

I agree with people who believe that Hank is speaking too quickly in his videos, therefore making it hard to grasp information (especially if you're LEARNING the material, instead of revising it). This problem can be solved by clicking at the end of the link of the video and manually typing in 'slow' (it works for me). Anyhow, I am still grateful that CC had made these videos easily accessible and available for free. Thank you CrashCourse!

[@jcmorales1564]

Halogens have a very high ionization energy (not low, as written on the periodic table at 4:54). Only the noble gases have higher ionization energies. Ionization energy is the amount of energy required to remove an electron from an atom. So, it is very difficult to remove electrons from the halogens, and even more so from the noble gases. In contrast, the alkalis have very low ionization energies. Great video! Thank you!

[@27Nichy]

I might yet pass my Chemical Principles retake because of this series. Thank you guys so much, you're my only hope and I have lots of hope!

[@shruthibarathan1997]

I read "my Chemical principles" as "My Chemical Romance" oh no

[@christopherrobinson193]

When you balance the number of Electrons in the N2 --> 2NH3 reaction. Shouldn't there be 6e on the left side? Because 2*-3 = 6e

[@swampertblaziken1]

Right!

[@alvinmoore308]

Yes, it actually should be 6e in each of the NH3 equations. N2 is reduced, gaining 6e, and 3 H2 is oxidized, giving off six electrons.

[@ShuAsohlinda-jx9ov]

This is a live saver thank you very much I have learned a lot

[@cr9ngey925]

wow i am new and also dont know who name is that guy but his good at math and science 😮i impressed MIND BLOWN 😮🌡🌡💣💣💣

[@einavguetta3500]

Crash course is a gift for students with teachers who don't give a fuck

[@JimNagle87]

Thumbs up if you love the way he says "Noo!" at 5:35

[@veronicaecheverria594]

Wow, I love you. Love your humor. Thank you.

[@kimbrownct1]

I would love if there was a possible specific crash course chemistry made where it slows it down and goes more in depth. I lost you after oxidation numbers/states and rules. But that mostly because I'm trying to remember undergrad chemistry from 5 years ago now. Love this series so much.

[@MichelCarroll]

This was incredibly entertaining! Thought my review on redox reactions would be dull.

[@tolinhnguyen79]

Thank you Hank !

[@SarahSkye14]

With 10.5 hours to study for a Chem 2 final after Zoology and Biostats today, Crash Course is the best thing in the world! He's got all the stuff from Chem 1 I forgot explained in a memorable way for visual learners.

[@shengxd9068]

informative video but everything goes too fast

[@AlbinosaurusR3X]

+Ce Sheng (Jackson Foo) Yeah, he sounds rushed when this kind of material takes time to process.

[@Novjuly]

That's why I have to pause and let it sink in before I replay it. :)

[@araeside6979]

Just watch it over and over again, write down the key notes and let it sink in.

[@mahisolomon8819]

+Ce Sheng (Jackson Foo) you can slow it down by using the setting in toolbar although it might sound weird.

[@williscorto4540]

+Ce Sheng (Jackson Foo) You cant expect to fully understand these all in one viewing.. its like being upset that, after your first physics class, your still no Michio Kaku.

[@Auhailbree]

maybe if i watch it a fifth time...

[@GA-kx8yh]

If you can just cover all of my gcse topics would be perfect.Seriously though you make all my topics so much more interesting and easier to understand!!!

[@barbellbilly]

CrashCourse your analogies and illustrations have htruly helped a dummy like me who couldn't have learn this stuff otherwise, seriously. Thank you. =]

[@aspenhunter9322]

the little animations are so cute

[@2b-coeur]

+Aspen Summer I know right?

[@JohnsCobras]

Too fast... Slow down please.......

[@SoraShadowdancer]

But chemistry excites him!

[@elsie3916]

Pause button?

[@JohnnyDoeDoeDoe]

He prefaces units with saying that if he's too fast you can always rewind, re-watch and even play in slow motion using the options tab.

[@SamuelGavin]

Its hilarious to watch him when you change the speed to x0.5.... sounds like he is drunk XD

[@Madisyn7]

Predator11563 he would make life easier if he just slows down a tad lol but otherwise hes good :)

[@kevinharris6650]

My graduate level professor linked us to this video for class. the course is intro to environmental systems and the professor knows most of us have not had chem in forever. great video.

[@boringlikeme]

Hank, you're the awesomeness in person. Thank you for existing.

[@oldcowbb]

trump before he is a meme

[@pauljones3017]

He still is.

[@shuriken188]

I believe they mean that CC Chem is joking about Trump before the time in which he was a meme.

[@lukeberlin2120]

Do you mean before he is president?

[@sameersheikh5301]

Is the guy at 0:07 Donald Trump? If so, then I love CrashCourse even more now.

[@Giacomino_]

+Golam, In Brackets Yep, that's definitly Trump.

[@sameersheikh5301]

Matthew Miller Awesome! I love how they did his hair.

[@rynsawyer4185]

+Golam, In Brackets Well then you love CC even more, cos it is Trump

[@sameersheikh5301]

Lauryn Sawyer Yay!

[@gabrocki]

#MakeChemistryGreatAgain

[@SOMEWHATALICE]

watching at 3am and i don't even mind (gcses in a month)

[@santiagodaceprano3917]

Same here lol

[@zhencongng8064]

you are hardworking

[@AJayZy]

Or you know, desperate.

[@SOMEWHATALICE]

yeah haha, desperate but it didn't come up

[@johng.8626]

Watching these to pass time and gain knowledge of chemistry. I don't ever plan on being a chemist so I get a bit glossy eyed when he starts doing the math part of it. I don't envy anyone trying to learn how to calculate these reactions by watching this video.

[@swampertblaziken1]

To anyone complaining that the talking's too fast, remember that it is just a crash course, and since this is a video, we're welcome to rewind to whenever we want to be. In a typical CrashCourse video, I rewind around 30-40 times within the whole vid just to make sure that I absorb what he wants to say. You are not expected to get all of the lessons from the video in one sitting. Have patience, guys!

[@kylecai2727]

how did i get here from watching "i want it that way" from back street boys....

[@Cara.314]

Because KZbin felt that you had better things to do with your time.

[@quantum_psi]

half reactions are fucking hard, go slower please....

[@sega310982]

0.5X speed

[@quantum_psi]

i did, but he sounded too drunk

[@justanotherguy965]

Sebastian Gulbransen Haha, I tried that now. Sounds totally pissed... and the intro music too!

[@MrCrazytodd]

sega310982 Lol. How do you do that? (slow down the video)

[@sega310982]

Todd Gobbett Click the gear on the video and set the speed.

[@rafaelximenes6550]

Oxygen can have a positive charge, when it's bonded with fluorine, because this last is more electronegative.

[@steadycheckmate]

After hearing you speak every sentence, I felt like taking a DEEP breath -- you spoke really, really fast. Good video though!

[@jamba3817]

thank you this video has saved me for down the road...i wish i found this before my exam yesterday...

[@mikkicarr5717]

Third grade algebra? Who learns algebra in third grade? When I was in grade 3 we were just learning how to multiply!

[@aeroscience9834]

Can you get silver from the silver chloride in the previous video?

[@niloygomes3625]

+Aeroscience I'm not sure about this, but electrolysis might work.

[@yousufalwaheb8394]

+Aeroscience search for selective precipitation

[@mal9310]

and this is where I give up on chemistry again :(

[@nardo7817]

Reduction is called "reduction", not because of the change in electrons, but rather in the oxidation number. When an atom is reduced, so does the oxidation number. Can't say for sure about "oxidation" though.

[@brishti_chakraborty]

Reduction/Reduced: The charge of the atom gets reduced. Oxidation/Oxidized: Being like oxygen (oxygen takes electrons). One definition of -ized means "to become like". Hope that helps.

[@impatientjones1617]

When you have a Chem final and are trying to find the easiest way to study. Thanks Hank.

[@LegoSwordViedos]

Well time to go take my final.

[@ilomaster6]

for someone who's new with redox-reactions,its gonna be difficult to follow cause he's going TO FAST en he talks a lot whats irrelevant with the subject. And showing the reactions weren't so good he made it like puzzle. now for someone who's new with the redoxreactions ,and you make it like a puzzle,well lemme tell you this HE WONT BE ABLE TO FOLLOW. the video is good but you should make it more easier to follow :)

[@willparker9874]

calling reduction "reduction" does make sense if you consider the atom's/ molecule's charge is being reduced as it gains a negative ion. Mg is reduced to Mg^2-

[@OnTheHorizonMC]

In my class, we use " *LEO* the lion goes *GER*" (cuz our school mascot is a lion). *LEO*: Losing Electrons, Oxidation *GER*: Gaining Electrons, Reduction Idk, it helps me remember the oxidizing agents and reducing agents better. *OIL* *RIG* is good too though.

[@bethli244]

Best way to study for finals

[@ranudisenanayake5181]

LEO said GER

[@jaybestemployee]

Here's my honest advice to the host. There are 2 cases I consider the quality of this series. When I am already familiar with the topic/concept, I feel the host is just telling bad jokes about it. When I am NOT familiar with the topic, what the host said didn't make it easier to understand. It seems the host is not trying to make people understand new things but just to let them hear you skim through all those keywords that can't be understood without prior knowledge, with occasional bad jokes in between. I know there may be a lot of material to cover, but if you're going to make a useful video, either 1. tell better jokes with news/updated knowledge about the topic that those who already know chemistry would have missed because they are not up to date with news in the field; or 2. really patiently explain the concept in simple understandable well-paced language and well-explained examples like Phil Plait, another host of CrashCourse, did in his own field.

[@hannahg5407]

Four days before a high school assessment, this is a life saver!!!

[@almaszaveria5006]

Thank you so much for this, lots of love from 🇮🇳 India

[@qweteryFTW]

My Physics teacher said to think of oxidation and reduction as men and women. Men give electrons women gain electrons ...ya he was a pervert but i did learn something :D

[@donmckechnie9858]

An interesting Crash Course topic might be the burning of gasoline and the mass or (especially) the weight of the combustion products, CO2 and water.

[@FuzzyPanda962]

I realize this video's already been published so the point is moot but: I would request that for reaction problems that you show the overview of the reaction and maybe some of the parts moving as you talk rather than periodically cutting back to your (lovely) face. I'm a visual learner and that wasn't any easier to follow than my instructor's explanation.

[@gc4152]

great animation and topic thanks! (I suggest a slower rhythm instead of a constant speech which is tiresome, you would show more by merely focusing on the main points and alternating silence/music with talk).

[@mathewmjohn7322]

Guillaume Combot You can slow it down if you are on desktop. :)

[@ImperiumOfPenguin]

Anyone else finds it impossible to learn math from videos? I need to actually practice math, pen and paper style, in order to learn. =/

[@MrOhWhatTheHeck]

Definitely true for me. I'd choose a good textbook over a youtube tutorial any day.

[@robertjervis7443]

I would simply like to state that his speed and teaching is amazing for people who are currently or, even better, have already studied these topics. I noticed a LOT of people complain about his speed which is very justified(he does speak really fast) but I have also noticed a lot of people complaining that he isn't great at teaching where in fact it is a crash course im going to assume intended for people trying to get better (meaning you've already studied these topics) or, like me, people who are trying to get a re-fresh for university but not really the best thing for people trying to learn from scratch. BUT that's just my opinion.

[@MrCrazytodd]

I also learned what a portmanteau is. Thank you.

[@TheGamerUnknown]

I pay attention, and I watch it a few times, but damn i can't get a hang of it. However, this isn't something we cover in AP Chem. Atleast if we do later on in the year, I'll be more prepared. Thanks you. :)

[@youvegot]

watching this during the election and laughing at trump

[@BlappetureCO]

me hahah

[@youvegot]

lmao

[@Voyhkah]

well, sorry you-from-two-weeks-ago, but in my time, we've stopped laughing and are curled up whimpering.

[@youvegot]

***** I know, I can't believe he made it so far.

[@KittySquires]

Sorry you from two days ago...

[@JoeyCha]

John's college girlfriend and Trump at 3:57

[@jessicahernandezmorales4664]

Thank you so much. This is helping a lot. :) My professor teaches too fast sometimes, but at least here I can press pause.

[@angelsquad1o110]

Can believe this was made 10 years ago

[@TonboIV]

The Trump animations are suddenly much less funny.

[@SS-hv5sy]

why

[@dainironfoot5198]

@@SS-hv5sy Have you been living under a rock?

[@SS-hv5sy]

@@dainironfoot5198 he got rich so what if he is president .

[@TonboIV]

@@SS-hv5sy I suppose the situation looks a little different if you're a neo-nazi. You even have SS runes for your AV.

[@PengyDraws]

@@TonboIV you, assuming only white nationalists support trump: half of america: kek

[@triad6425]

LEO the lion goes GER. that's how we do it in my hood.

[@zappchance]

meaning?

[@zappchance]

Thanks!

[@calorus]

Losing Electrons Oxidises, Gaining Electrons Reduces.

[@gmanmchugh]

0:05 "What they're willing to do to get it" ... like become president

[@unknownforeverrr]

how would you know how many electrons to add, like for the n^2 example why is it 3 electrons

[@MrHolozip]

made it to 6mins before my eyes glazed over...