Calculating Average Atomic Mass

This video demonstrates how to calculate the average atomic mass (also called the relative atomic mass) for an element. It also demonstrates how to determine the most abundant isotope of an element.

[@fAnTaGeChRiStInA0319]

your voice sounds like alex vause's from oitnb :D
& this was also really helpful

[@Carmen209cali]

OMG Thank you, YOU SAVED my life right now, you did great explaining this. It's easier than what I thought.

[@dayme484]

me seeing that this saved people even 10 years ago😳

[@Waffle2Ninja]

Helped so much, thank you!

[@chrisgarcia1232]

thank you so much really helpful
:)

[@vaibhav2831]

Best explaination on youtube

[@AndyDaxter]

Will the percent abundance always be the same no matter how much sample of copper you obtained? How was the mass of each isotope determined in the copper example?

[@yorkiedanMC]

when i typed the numbers into a cal i got for the first one 1,894.576269 the deciaml point is different to yours ?

[@becomingeco-friendly]

Thank you so much Lisa! Very helpful tut.

[@YouTuberOnlineNow]

how did you get the abundance? How am I supposed to figure that out? I understand the how to find the mass but I don't understand how you got each part (the abundance and the mass) before you did the calculation. I'm more confused then what i started out with in chemistry
.

[@skeeterburke]

abundances of isotopes are usually determined with a mass spectrometer. basically, dig stuff out of the ground, stick it in a mass spectrometer, and let the machine count the isotopes for you. clear as mud, right? what's really crazy is you get close to the same answer no matter where your sample came from, whether the bottom of the ocean or the top of a mountain. study hard get good grades go to college learn how to pull a vacuum then they let you mess with chemicals, fun stuff

[@0009Muhammad]

wait, how did you get the mass of each Mg???

[@livvystevens17]

UnknownHero trying to work that out myself

[@abibatallim6971]

EXACTLY

[@HunterLukenbill]

Its not something we can inherently figure out. The masses have been calculated over the course of years with many scientists collaborating around the world. You will have to look them up somehow or have them provided for you.

[@skeeterburke]

each isotope has their own binding energy, otherwise you would add the weights of all the protons neutrons and electrons, but the mass of an isotope is about equal to the sum of all these masses. i'm not a particle physicist, but i think there's some particle theory that attempts to explain why the binding energy is what it is, and uses observations of binding energy to model the strong and weak forces (the two fundamental forces that act inside the nucleus) - i probably butchered that and have some particle physicists laughing at my post, glad i could offer some comic relief!

[@kachetusimeon8912]

Great explanations.. Understand perfectly.. Woo - huu

[@penehafojohannes5468]

Hmmm🙊 I ci u r a fan of online videos too...thought I was da only one

[@kachetusimeon8912]

+Laudika Johannes yeah I like them as they help in situations where teachers aren't available to explain again...

[@reemoo123]

thank u so much

[@ODDthoughts3]

Life Saver thankies forever dude!

[@tonygueco1096]

thehumeinbrein hey I say that too

[@nickane6]

You never explained how you got the mass...

[@stigma3216]

A bit late to your question but you simply turn the abundance percentage into a decimal by bumping the decimal over by two spaces. Like %78.99 would be .7899

[@stigma3216]

Then take the isotopes number and multiply

[@madisonlewis4987]

@@stigma3216 THANK YOU

[@sathyavenukrishnansathyave1060]

Same question for me

[@madisonlewis4987]

@@sathyavenukrishnansathyave1060 i read on reddit that you cant calculate the mass by yourself youll either be given the mass of the isotope or be required to look it up.

[@louisb5846]

thanks!

[@mehdiachouri]

if you didn't get that you should forget about chemistry. and you should be respectful to this lady she just wanted to help even though she didn't have to.

[@mehdiachouri]

thank you Dr Lisa, may god help you with whatever you need help with, same way you helped me and lots of people around the world.

[@stevevnguyen]

i have a question. what if i have an isotope of uranium 235 with the natural abundance given, but not the atomic mass. How could i figure that out? thanks

[@KyleSimon606]

The isotopic masses are experimentally determined values that you can look up online if they aren't given to you.

[@t.c.5456]

Great explanation

[@asaniblake4086]

i dont get it there is no explanation on how to find the abundance

[@user-zo2fs6jd2r]

How did she get the mass?

[@dw-rh6fb]

Basically, if you dig up 2 piles of Mg that both look exactly equal (atoms count is equal), they may weigh different amounts. Weights are ambiguous, making mass ambiguous being that gravity doesn't vary but weight does. You have effectively shown that if you take exactly equal amounts atoms of an element, the isotopes will give you something that looks the same, but does not weigh the same (mass isn't equal). That is really interesting.

[@livvystevens17]

This Tyler Oakley? 😂

[@iloathbirdsss]

U rack disaprin!!

[@tclement1989]

Lady if you marry me right now...im guaranteed to pass my Gchem....thanks for post....my GChem professor always ninjas my brain...i got this....

[@expertbytcare9567]

Hi

[@indaymarlyn6801]

24.30 not 24.31

[@qbhi___]

marlyn pablo its .31 the round off rules waa add 1 if the next decimal num is 5 or higher

[@indaymarlyn6801]

Chester C thank u.😚

[@PeytonManningguy]

whos in mrs hammers class??

[@azizkash286]

UwU

[@ms.waidabeauty]

I’m so confused 😐 I very much dis like chem

[@mkattietaylor82]

Your inability to focus is HER fault?

[@podstheking957]

Shit, I'm triggered after watching this video.