Unit Conversion & Significant Figures: Crash Course Chemistry #2
Вставка
- Опубліковано 7 чер 2024
- A unit is a frequently arbitrary designation we have given to something to convey a definite magnitude of a physical quantity and every quantity can be expressed in terms of the seven base units that are contained in the international system of units. Hank thinks this is a thrilling subject, and while you may not agree, it is a subject that is very important if you want to be a scientist and communicate with accuracy and precision with other scientists. So listen up and learn something or Hank might have to kill you! (NOT REALLY!)
Watch this video in Spanish on our new Crash Course en Español channel! • Conversión de unidades...
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
Table of Contents
Unit Conversion 02:27
Scientific Notation 03:26
Sig Figs 07:40
Crash Course is on Patreon! You can support us directly by signing up at / crashcourse
Want to find Crash Course elsewhere on the internet?
Facebook - / youtubecrashcourse
Twitter - / thecrashcourse
Instagram - / thecrashcourse
CC Kids: / crashcoursekids
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
k
YESSSSSSSSSSS
Very nice
Hank in 2013: "maybe 50-100k views"
2019: 2.7M views
2020: 3M
You mean 2.7*10^6?
Timur The Terrible we love our profile picture
I'll remember that next time when I fail my test: "At least you didn't fail your mission to Mars" lmao
What’s this is reference to?
Fr tho
"Do you know what we do to liars in Chemistry? We kill them" -Hank Green
Should've been my senior quote smh
I was about to comment that
Like accidentally, right?
yet, that's just besides the point.
simplymaci tyler smith was first.
simplymaci its gonna be mine 😂
When Hank established his street cred
5:26 Calculator says boobs.... very funny Hank.
everyone is low-key immature
05:29
5:30
BIG OOf
Jason Hurle it says 80065
"-And you know what we do with liars in chemistry? We kill them" -Hank, 2015
Tyler Smith Best quote ever!
*****
I fell down laughing after reading that
Ok now im obligated to tell you a chemisty joke
Did you know alcohol isnt the problem.
Its the solution!
You Crash Course guys should make a site that tests us on the information so we can see how much we are absorbing from each episode. (Yes, I'm that person that WANTS to test.) Thank ya'll and keep up the good work!
Khan academy
I want it too!
I agree with you on this one.Crash Course please do it
it happened now lol
They made an app
When you have a chemistry test tomorrow and you don't understand sig figs so much you use Hank to help
ME AF. Lmao, I have my first exam for chem fall. I'm freaking out because conversions and significant figures bug me. I'm just going to kms
girl same
Kaitlyn Carroll get better at maths
Kaitlyn Carroll same tho
Me😂
I swear Crash Course is the only reason I'm doing well in school
Sarah Fullerton-Barrios 👏👏👏
I’m still a bit confused because my teacher haven’t taught me this yet.
Well , how well?
So true
*tells a lie in chemistry class*
*remembers this video*
*starts sweating profusely*
We don't kill liars in Chemistry... we Barium. Missed obvious joke opportunity.
Hahahahahahah!!! That is a great pun!
My teacher told us one simmilar to that. it's "What do you do with a sick chemist? Well if you can't Curium, and you can't Helium, you might as well Barium."
thats not funny
Michael akinkunmi Yes it is.
Lol
you have explained sig figs better then my teacher and i'm taking a summer class for chemistry. I'm awful at it. Thank you.
completely agree with the sig figs thing
i have to use outside resources to understand what was taught in class
and i thought ib chemistry hl was difficult just because it was ib chemistry hl
I came here to help with chemistry but I was also struggling with unit conversions in physics
oh no baby what is you doing??
Wait. Your name can be spelled with a lowercase letter. Green or green. Name or color. So you are a great person.
50-100k views: Hank's prediction.
1000000 views: reality
+LJ Fleming Which means a solid 70 to 140 people did the math along with him.
Professor Syndicate Yep
More like 7.0 x 10^1 - 1.4 x 10^2
needpit1 Yep
+LJ Fleming my tought exactly. exept for the current ammount of 1,22 million (yeah, its a comme over there, greets from europe. lets wait for a unification on to settle this topic someday)
"50 to 100 thousand views"
*video has nearly 650 thousand views*
UPDATE: *video has nearly 2 mil views*
It is sad that this doesn't even have a million views and Justin Bieber has 3-4 million views. mariaarakal
FROP DESAI tru dat
FROP DESAI How is that sad?
mariaarakal modesty
SpadaccinoLuciano It's sad because Justin Beiber has absolutely no talent and does not deserve the number of views/followers he has.
"And do you know what we do with liars in chemistry? We kill them!"
-Hank Green 2013
Awesome!
This still bugs me. They added an annotation correcting the 310 error, but there's no annotation for the light years per second calculation. They got the completely wrong number for it! The correct answer should've been 2.8 x 10^-15 ly/sec, it is not 9.3 x 10^-12 ly/sec. *_It's been nearly 4 years now, how am I the only one that's noticed this!_*
THANK YOU!! I was just resolving this problem for 30 min and kept getting the same answer- and this is the only comment addressing it
Annie Reller Lol! Maybe we really are only two of the seven people that worked along with Hank on our calculator. I remember noticing this mistake when the video was first uploaded back in 2013, I'm shocked that no one's pointed it out to Hank by now.
+David Bridges haha wow, i just spent an hour doing that problem over and over i thought i was doing something wrong
I agree he messed up the calculation.
THANK YOU I THOUGHT I WAS CRAZY AND imalready confused so that why i watched this video and i was freaking out cause i though i finally got it but it wasnt what he got haha
"You know what we do with liars in Chemistry? We kill them"- Hank Green, secretly a supervillain.
Hank: Do you know what we do with liars in Chemistry?
Me: What, Hank? This is bound to be witty.
Hank: We kill them.
Me: Oh. *terrified*
I thought he was going to say we Barium
gamerathletemusician lol
"You know what we do with liars in chemistry?"
WAS REALLY WAITING FOR YOU TO SAY "BARIUM" HANK
c'mon. oldest chemistry joke in the book. :p
but also, very good video! I've been watching your series all night. Thank you for teaching me in a way my chem professor couldn't.
In chemistry, we kill liars by pouring strong acids on them, followed by titrating some bases on their bodies
savage
Or we put them in a thing of boiling steel
nah thats totally a lye...
thus, finally making them neutral
But after reacting an acid with base there is a formation of salt, so what happened to it?
Let's create a new unit of measurement called: the hank!
The hank is a unit representing one actual view of a youtube video, for each predicted view.
I would suggest "greens" as a measurement of awesome.
+Pink Wings I'd go with hank.
This video has 1.2624 x 10^1 hanks.
12.6688 hanks now
Pink Wings Who the eff is Hank?
am i the only one who to understand this has to wtach like 3 times.
then in slow motion. then backwards. then ask my father. then not understand and move to next episode?
What didn't you understand? Units or Significant Figures?
Yeah you sound like me. Keep trying though. Im persevering with Science and Maths because i have a genuine interest even though they make me feel like im thick..
You are not alone. But trust me, just paying attention in math, physics and chemistry in school, and some practice (homework), will make this a very simple subject. Everything is challenging at first.
Ask questions of what you don't understand, im sure a lot of people will be willing to help you.
Pause when you have to take something in which you know you won't understand just by quickly brushing past it. It helps me to write it down also for reference.
I only just started taking college level chemistry and thought my teacher was just being overly stern about representing significant figures. Now I realize he's actually trying to save my life.
"Do you know what we do to liars in Chemistry? We kill them" - Hank Green. Very good teacher. Hank Green for president!
I've watched this episode around 7 times, and now I understand it finally. Thanks for these videos Crash Course Crew! It's really helped a lot!
God, I wish you were my Science/ chemistry/ bio/ teacher. -_- OH you should do world tours. Not just in university's though. Like in high-schools and stuff.
And what you Americans call' idle school'!
Iffshah Jaffery Oh lol you mean middle school? That's grade 7 and 8 in Canada. :D I'm not American. :P AND he should do world-tours in America too YES
With us learning so much using all types of science, there is WAY more to learn than when I was that young... We all should keep up with science, but it's going so fast now. That new show 'Cosmos' should inspire a LOT of people, it might sound irrelevant but it's a really good show I wish I could've seen when I was young.
AquiredCents Yeah I've seen that show! It was amazing! It really made me think a lot about astronomy and whats really out there in the big wide universe.
Inayah Cee I'm British...
I love that he opened with the often overlooked fact that units of measurement are completely arbitrary. Got my attention right away. I've never understood significant figures before today, and now it makes perfect sense! Thank you!
The difference between watching this at the first week of chemistry class and the 4th week of chemistry class is remarkable... Literally helping me study for my second test.
Please tell me someone else saw it at 5:30
+Colin Warn Took me some time, but yeah.
+Colin Warn thanks for the good laugh Colin!
( ͡° ͜ʖ ͡°)
Hah yep, I just opened the comments to see if anyone else did. 80085!
What did you see????
I love my chemistry professor, but.. I'm just learning better here. This guy's sense of humor cracks me up.
The editing,the music,the teaching and all these stuff are amazing and i just love them 😄
myself and my college pro love your videos.
we discuss almost weekly in class about you and how you make it easier to learn
or how what we are doing in class relates to what we have seen on crash course !
i encourage my class mates to also watch these videos
but light years are also arbitrary, because years are arbitrary.
i laughed but then i realised light years is measure by speed of light, so speed of light isnt arbitary?
Brian Ung it's the speed of light per year. now the speed of light part is probably the least arbitrary thing you could pick, but i've got a problem with the year part. our year is based on the time it takes for this one particular planet to make one trip around our star. that part is completely arbitrary.
Huntracony
but the "year" is a set amount of hours, minutes, and seconds. albeit an amount of time that, if measured now, would differ from the original or standard calculation. but while our planetary rotation may have changed, the speed at which light is capable of traveling within that arbitrary, but defined, figure remains constant... Or does it?
Geordi La Forge well, in leap years light suddenly gets a whole other day to travel, which suddenly increases the distance of the lightyear. so even though the speed of light remains constant, the lightyear does not. now that's of course not how it works in science because it'd mes everything up, but that is what a lightyear is.
A year is the amount of time it takes for the earth to make a complete orbit around the sun. New year is arbitrary.
I didn't realize Crash Course had a chemistry video on unit conversions and when I found this I nearly started crying out of happiness. Unit conversions are very difficult for me.
Hank, you're the GOAT. Please don't ever stop posting these videos
I am fairly new to CrashCourse. I started watching last year for Anatomy and the body systems. I did really well because of CrashCourse. So, here I am, back again, thrilled to find Chemistry by CrashCourse! This was one of my favourites. Simply because of "...what we do to liars in Chemistry...". I laugh so much through the episodes my family wonder what is wrong with me!
I just wanted to say, I've been watching you SciShow for over a year now, and now since I just started honors Chem, it is so cool to actually learn school information for you. It is like you have moved from the entertainment part of my life to the school part, which is a really weird feeling. My chemistry class is already very interesting, but now my brain is processing it as raw entertainment. And for that I thank you.
Genuinely,
Paul Wyrough
I love crash course you guys are so dedicated to learning and you make learning really fun, thanks Hank and John :)
I know almost nothing about chemistry, I suck at math, and I did not find this episode - or any of the ones I have watched thus far - difficult to comprehend at all. Thank you. :)
Crash course has literally everything that I need! Thank you!
Maybe an annotation is needed to correct the start of the video - the IPK no longer defines the kilogram, it is now defined as 6.0221408418x10^23 atoms of silicon-28 (Avogadro's Constant).
***** www.nist.gov/pml/si-redef/kg_new_silicon.cfm
You made me love Chemistry. Thank you.
This is my favorite video on this channel (of the ones I've watched so far)! Thank you!
You set it up so nicely for a good chemistry pun! "You know what we do with liars in chemistry? We barium."
you explained more to me in 11 minutes then my chemistry professor did in 50 minutes, thank you so much.
I still don't get it.
Omg please become my teacher, I LOVE YOU!! You're just so entertaining and make it all so easy to listen to!!! I've never enjoyed chemistry so much in my entire life!! Hopefully, I'll be able to get ready for my medicine entrance test thanks to your lessons!
Studying for the TEAS Exam for Nursing School. I haven't taken a Chemistry class since HS, about 10 years ago. Thanks for ALL your help!
watching an episode every day it's actually fun to learn
It took 11 minutes for him to explain something that took my chemistry teacher 6 weeks to teach. ahh the wonders of the internet.
Dude, you are genuinely funny; it never detracts from the point, and it always catches me by surprise!
absolutely love this whole channel. great work
Him: Uses calculator to calculate complex numbers...
Me, a CBSE student: What is this sorcery?
I am refreshing my brain with this videos, I find them Quite interesting. and like my dad always says , you have to learn twice , once you are a kid and second when you are a dad.
I didn't understand scientific notation or sig figs before this video, VERY HELPFUL!
Thank you for making this video, Hank Green and all the others at _Crash Course_ Chemistry! To be honest, this felt more like a mathematics lesson than a chemistry one, but anyways, thank you. I learned the different between measured values and exact values and when to use each one and I actually think this is going to help me very much on my next math exam. Also, I never though of the SI as arbitrary before, but come to think of it, your right. There is nothing in the Universe that says a kilogram has to weight just that much. It just that I have always though at the metric units as logical, and I do still think they are more logical to use than the US standards, but I never realised that most systems are really illogical. THank you!
There's the thing saying sorry about them messing up the number and stuff, then he proceeds to say, "And do you know what we do with liars in chemistry? We kill them". Hank, I'm sorry in advance for what's going to happen.
WOw your crash course of chemistry is very useful for me... thanks Crank.
This is amazing! Thank you Hank and team!
Amazingly helpful! Thank you CrashCourse!
"We kill them." I really never thought I would hear those words from Hank.
i swear this helped me so much more than a whole chem class period😭😭🙏tysm
The examples shown, I didn't really understand fully until the third was shown. This is actually really helpful. Thanks.
I love Crash Course! It explains it to me! Thank you Crash Course :)
who else is watching this for homework right now
I tried the physics course... the way she explains things put me off a little. The Green Bros (and Stan) are so much more clear, I don't know why.
I love this series. Thank you!!!
Omgggg this made everything so much better!!!! Thank you I understand everything so much better.
"And you know what we do to liars in chemistry? We kill them."
Suddenly I'm not as interested in chemistry.
50,000 - 100,000 people he says. 1.1 million there are... You modest person.
2.6mil
@@travisstroman-spaniel6091 3 mil now
Love your videos I'm terrible in chemistry and these videos have been very helpful to make the material easier to understand.
Would love one on the metric system in general (base units and prefix conversions). Love your videos and use them with my students regularly.
what do we do with liars in chemistry........"WE KILL THEM".....
D then w barium (yeah I am sorry all the other good chemistry buns argon )
+crazysquirrel I hope these jokes don't come periodically
I slapped my neon that one. It was sodium funny
@@plantymcplantface7182 I hate all of you.
Anyone else do Hank's process for turning 60 MPH into Light years/second and get a different answer than he did. I got 2.82e-15, anyone else?
i had never understood sig figs in my life but he is the one who explained it to me. I had been listening for all the video not understanding when he talked about liars and i just grasped the whole point thnx hank
Absolutely amazing, thank you for the help
No we barium
U guys should do videos on physics!!
Thank you Hank, they teach this at school but I never really understand the use until just now
That was truly delightful.
Mom: What did you learn from the chemistry video today?
Me: Today we learnt that we kill liars in Chemistry!
9:55 - I understand that we need to round to 2 sig figs in the final answer, but I thought you round the answer to 310 or 3.1x10^2? I thought you do that because the 5 in the ones place is right next to the 0 in the tens place, so you round up?
Your videos help me so much and I’m confident I won’t fail
wow, so it’s really THIS easy?! my professor made this sound like a foreign language!!! thank you
Had trouble figuring out how you calculated the conversion into light years.
same, can someone please explain?
okay got it he multiplied it but the answer is wrong it's supposed to be 2.84 x10^-12
Hi there, I got the same answer as you, except with 10^-15, even after I put the conversion through Google. Can you please confirm, or is there something important I'm missing? Thanks!
I got 2.82x10^-15 every time I did it also.
Same..I'm so lost
how did hank go from 60 mph to 9.3 X 10^12 light years per second? I tried the math on my calculator, and I got 2.82485876 X 10^-15.
+Brian Lee so did I, I thought it was my error!!
Goddammit Hank. You know what we do to liars in chemistry, right?
so did I
I did as well. So annoyed cause I spent 15 minutes stressing about how to find the right answer. It really ISN'T as simple as "hammering" figures into a calculator!!
+Brian Lee
Most of the time, students enter the number into the calculator in the wrong order of operations. Use parentheses liberally.
I have AP Chem in school this year and I haven't take Chemistry before so thank you for doing this!
OMG i only watched 2 vids and i already love these eps!!!
This was beautiful...
Well said rainbow dash, well said
agree that km/h isnt much better, but it is easier to convert to lower units because of the standard base of si units(10). Converting miles to inches on the other hand, good luck.
I understand so many things I didn't before! Thank you so much! 🤓
Correct me if I am wrong, but at 10:00, I believe the actual number should be rounded up before the insignificant figures are omitted, which makes the number 3.1x10^ 2.
I thought this was the definition of a second: The second is the duration of 9 192 631 770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom.
+arjenbij ... yes I'm so going to use that on my test
+arjenbij and the meter is defined as 1/299,792,458th of the distance light travels in a second (or the distance travelled in 1/299... seconds). Other definitions are still being worked on, though I believe two other constants are being based on planck length and the elementary charge.
I'm not sure of the exact count, but yes, time and distance have been defined by counts of the hyperfine state resonance in an inertial frame and the speed of light. Those might not be absolutely constant, but sure seem to be.
I'm gonna need you to take over for my current chemistry teacher. Lol
Wanted to drop by and say thanks for the quick review. Helped a lot!
Love this show really helpful Hank Green
"You know what we do to liars in chemistry... We kill them" OMG I DIED
I assume you are a liar?
Maybe is my brain fault, but I can not calculate9.3*10^-12 at 5:02. I only got 2.82*10^-15
Same.
You are a good explainer Hank! Nice job... Keep Up! 😊
I can't thank you enough for making these videos