V5K7J2

[MrBlade0001]

Shouldn't be 7.7625 * 10^-11 mol of Zn instead of 7.7625 * 10^-13 mol of Zn?

[glowingdarkmatter25]

If Avogadro's number is at 6.02 X10^23 why doesn't it change when you round it to 24...why is it one mole ? or is it more than a mole....

[Accidulation]

You are a great teacher! Much better than the one I have teaching me. Thank you so much for your videos, you have been of such great help! Keep making more videos! Thanks!

[shubh008]

the enthusiasm and energy level with which you teach is really appreciable!!!

keep loading thes awesome wids....chemguy

[panikku11]

I LOVE your energy, I learn so much more from you than my chem teacher..

[notafraidtouseit]

ur going to be immortal !

[328450J]

is converting atoms and molecules the same?

[bannanaiscool]

@328450J Pretty much!

Chemguy

[roso614]

wouldn't it be -12 not -13

[angelsgirl515]

Thank you sooooooooo much for making these videos! You have no idea how much you are helping me!!!!! Thank you God bless!!

[RoayaPixel]

you are the best i would have failed without you , and im an A's student!

[HuckHuckBoomJam]

That's my friend Ryan

[Panzer0127]

Now once i've watched ur videos my teachers look crap.

Where do u teach i wanna learn from you???

[shellylanette]

@Panzer0127 LOL YOU SAID IT!!!!!

[angelsgirl515]

@Panzer0127 LMAO I agree too!!

[majom9111]

@Panzer0127 maybe because they ARE crap? I know my teachers are.

IDK how they even got liscences to teach!!! XD

[helenJuice]

he makes it so interesting

[Shamali2009]

your just awesome:)

thank you soooooo much. plz keep it up.

[SmallTeaCupNo1]

dude i honestly wish you were my chem teacher. not only are your videos getting me through class, but they're fun to watch and easy to understand.

please dont stop, its great.

[Youcantbeseriousa123]

I am probably the only one in the world getting this wrong but I come up with 7.7625x10^33 :( where does the -13 come from?

[bannanaiscool]

You're punching it in backwards...Think about how 10^11 atoms of Zn would be far less than one mole of Zn (which would be 6.02x10^23 atoms, right?) Your answer says that there's more than a mole, not less. Try again and watch your exponents...

Chemguy

[anna258]

lol, he keeps on swearing at me!

[akosiivanangeles001]

damn.. your better than our teacher :P

[kz651]

Way better explanation than the book or my teacher

[kingdomheartsfangrl6]

thank you!!!

This helps me so muuch!! I FINALLY UNDERSTAND!!!

[BugetProductions]

you got character, I like it

[cmreel]

isn't Avogadro's Number exact... infinite... not used to determine significant figures.

[bannanaiscool]

No. Absolutely not.

6.02 has 3 significant digits. This is absolutely correct.

Chemguy

[alexis1azula]

thanx a bunch!!!

hmmm.... where can i find mole to mole, mass to mass, mass to mole, mole to mass and etc. ?

[360Sacleblu]

thank you for making vids like this... my techer shows us .. but u actually explain it

[twilyne]

You're great at explaining things.

[3halfshadows]

Thanks a bunch

[keerahogga]

your videos are really helpful and you teach with such enthusiasm! keep it up!

[Anuka37]

hii sir.. is it neccesary to consider the decimal numbers while calculating the molar mass.

will d anser vary......??

for example : while calculatin molar mass oh H2O D atomic mass of H is 1.01, can v take it as jus 1..??

plzz clear this doubt.....!!

[bannanaiscool]

If you're given the numbers, you have to use them! Have to!

No decision to be made! Do it!

How's that?

Chemguy

[Anuka37]

sir but in our school v use jus 1.. for hydrogen atomic number...

but u use 1.01.....

[hellokittyxoxox]

That's the average atomic weight based on all the isotopes of hydrogen taken into account. I doubt your school does this...it might just be your instructor. If you're doing calculations, you don't use just 1. Talk to your instructor and clue them in!

Chemguy

[layneheiny]

The teacher may not need a clue. There are reasons for using just "1." Rather than focusing on the mathematics, I try to focus on the chemistry. There are two reasons. In California, calculators are not allowed during the state content exam and students end up estimating. Plus, in my class, I have kids use the whole numbers so that we don't have to worry about which periodic table is being used (1, 1.0, 1.01, 1.008, etc).

[Anuka37]

i wish u ver my chemistry teacher.....!!!

[purefired]

isnt avagadro's number considered a conversion factor so you dont take it into consideration for sig figs?

[bannanaiscool]

Absolutely not! Avogadro's number, rounded to 3 sig digs is 6.02x10^23, but to 4 sig digs it's 6.022x10^23. It is not a "conversion factor", it's a number arrived at through measurement. Don't let anyone tell you different!

Chemguy

[becks787]

thank you

your video's are good

maybe a bit more explaining would be useful

[JaphethRS]

ok..u defined wat a teacher is..

[FicstheFan]

even tough ur not my teacher i have a quiz tmrw and i didnt get anythin from my teach soo ... i looked up on youtube and you were on and your amazing sir :P:) thanx for all the help

[OhowTragic]

thanks mr. Lederer =]

i hope i pass your quiz tomorrow

[ayooty93]

i cant understand anything what about the mole= mass/molar mass???????

[Eugene00159]

thanks sir, i hope i pass the semi final exam, hehhe

[kofixop]

so cool of u to take the time of making and posting this video ! thx

[jayknee25]

AWESOME

[Shivzster]

nice:) this is good review for the summer

[yvonniewah]

man, this guy is AWESOME.

all the confusion in my head has...gone!!

why can't all our chem teachers be like that huh?!

[xxdLLxx]

i actually said "you're amazing..." out loud. my parents were looking at me like wtf o.0

[Amandaes417]

i feel so much smarter after watching these videos

[KaMILFy]

Hydrogen's Molar Mass is 1.008.

[jumanjihock]

most people use 1.01

[montean3]

Universitys usually use 1..00794. and i'm in high school. bbut yeah this guys good my chem teacher is just as good but this guys way brighter and much less of a dick.

[telopeanAJ]

well its 1.00794

but like jimanjihock said 1.01 is more commonly used

[DKJ17]

good explanation.

[Phillamon10]

The mole concept confuses everyone, but when u explain it like that, It makes so much more sence!

[876437]

thanks man

[DaniFrano007]

you rock, i wish you were my teacher

[rym34]

This Guy is AWESOME!!!

[happieholly]

YOU ROCK!!!!!!

[MIZZIJR]

Thanks! we're learning about this tomorrow.

[pngndrtbkr]

ok exactly how much pot has this guy been smoking? hes way to happy about chemistry

but yes its a good video regardless of that

[manindergundhu]

wow you seem too happy about chemistry

but good explanation.

[meara33]

this is so helpful! thank you!!! so much easier than the formulas...are there any videos on %composition?

[Xmatthew315X]

So so so helpful! thanks!

midterm tomorrow! :S

[steevieweevile]

Then what is my teacher saying with n=m/M? What is that formula thingy! Thanks for the help, i get it now!

[gboy717]

thank u man

[facebook522]

you are Awsome....Luv YA

[ReHaN112]

sir can i please borrow your brain for my test????

[Deat401]

You make out teachers look like noobs ._.

[Yunior7]

Very easy to understand, we need more professors like you!

[aaromontes]

thank you so much!!! you help me study for my Chemistry Final Test I wish you could my teacher.....everything is much easier thanks!!

[gounc93]

I wish you were my teacher. Mine is so boring when she is teaching. Thank you for all of the videos

[peter73korea]

thank you so much

[echo707]

and thanks so much for the extremely helpful videos =) happy new year!

[echo707]

we need 16:9 HD chemguy

[bannanaiscool]

Yikes!  Wrinkle enhancement!

[ta1ntedxl0vee]

You succeeded teaching me in a mere fifteen minutes what my Chemistry teacher has failed to teach me all year.

Thanks, Chemguy!

[chriseatschopsuey]

same here

[majom9111]

@ta1ntedxl0vee Same here XD

Thanks Chemguy!!!

[dogtags4less]

Thanks ... Much appreciated ... wish u could teach my chem teach, on how to teach :)

[teshino9tweety]

hahaha... lol (when u switched accents xD)

[furiousharry]

wow thanks realy helped me, but it was a bit fast though lol

[bannanaiscool]

Watch it slower! ;-)

Chemguy

[mazzc7]

SORRY dont u get -12 when subtracting 11 from 23 please explain -13

[bannanaiscool]

Just do the multiplication of 7.76x10^-13 and Avogadro's number. You get 46.7x10^10, or 4.67x10^11. You're just forgetting that the number in front of the power of ten must be taken into account.

Chemguy.

[mazzc7]

thank you thank you thank you

[octopirock]

This is really helpful!

[bleachchampsun]

hmm i got 7.759X10 35 uhhhh wat did i do LOL

[MrsRich06]

hiya' quick question.. how did u end up with 10^-13? when we started off with 10^11??

[sciencehelp]

b/c 6.02 * 10^23 is at the bottom. using exponent rules of division you have to subract 23 by 11 getting -13 ( they both have the same base of 10)

[mazzc7]

THANK U!

[mewantpie1993]

Thank you SO MUCH!!! =D

You just saved my life! (I have an exam tomorrow.)

[sweetpromise4real]

u r a good teacher!!! thank u!!1

[chosandgooz]

Thaaaaank you !! you have no idea how much this helped me! You should be proud of yourself !

thanks again

/ a happy student !

[scradIey]

Great videos, love the fake German accent too, I lol'd.

[blackice122]

now i understand what moles are!! thanks a lot to bannanaiscool!!!

[Kelkaurine]

You are such a great Instructor!!!!