Effective Nuclear Charge and the Shielding Effect

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  • Опубліковано 24 гру 2024

КОМЕНТАРІ • 92

  • @AKLECTURES
    @AKLECTURES  12 років тому +2

    Hey! The only atom in which shielding does not occur is hydrogen, and that is because it has one electron. Speaking in very basic terms, you are absolutely right. The two electrons are found in the 1s orbital. But lets examine the ionization energies of the two electrons in hydrogen. If shielding does not occur in helium, that would mean that both electrons should require the same amount of energy to remove them. In reality (through experiments), the ionization energy of the first electron is

  • @AKLECTURES
    @AKLECTURES  11 років тому

    exactly!! most teachers force their students to memorize the trends because they either do not quite understand the effective nuclear charge themselves or cannot quite present it in a way that their students will understand it! I am glad to see that you understood the concept! Cheers

  • @adrenna05
    @adrenna05 11 років тому

    EXCELLENT video. You did a great job at explaining this concept. The Zeff explains all of the periodic trends that teachers teach students to memorize. This background information really allowed me to really understand the trends, not just memorize them. Thanks!!!

  • @AKLECTURES
    @AKLECTURES  12 років тому +1

    Thanks for watching! Im glad it helped :)

  • @AKLECTURES
    @AKLECTURES  12 років тому +1

    electron (the one further away) is only 1.34 while the effective nuclear charge on the first electron (after removing the second one) is 2. And this is once again, due to the fact that the first electron partly shields the second one from the full charge.

  • @kaylynpark8687
    @kaylynpark8687 10 років тому +8

    seriously one of the best explanations I have ever seen on youtube--thank you so much!

  • @Ashleethebeloved
    @Ashleethebeloved 10 років тому +2

    Your chemistry lesson was so good!!!! I did not understand Zeff and shielding at all, and you explained it so well. I am now confident with the information. Thank you.

    • @AKLECTURES
      @AKLECTURES  10 років тому +1

      That is great to hear Ashlee! :)

  • @marklandau365
    @marklandau365 8 років тому +2

    dang, this a great explanation. gonna watch this a few times! my professor is really good, but the class is kinda short so he doesn't have time to spend explaining things as well as you do. thank you Professor AK!

  • @AKLECTURES
    @AKLECTURES  11 років тому +1

    Hey! That is wonderful to hear. You are most welcome :)

  • @AKLECTURES
    @AKLECTURES  12 років тому +1

    24.6 electron volts and the ionization energy of the second electron is 54.4 eV. Why is this the case? Why does it require more than twice as much energy to remove the second electron than the first? The fact that the second electron is less tightly bound can be interpreted as a shielding effect!! This means that the other electron shields the second electron from the full charge of the proton nucleus. Once again, through experiments, we know that the effective nuclear charge on the second

  • @AKLECTURES
    @AKLECTURES  11 років тому +1

    Thanks! awesome to hear that!

  • @tarunnallur8834
    @tarunnallur8834 11 років тому

    honestly this was great. Thanks a lot. I also copied down the notes you had on the whiteboard . Some really good stuff . The greatest way to teach is to always put things in a simple way because than it shows real understanding and you have doen that.

  • @AKLECTURES
    @AKLECTURES  11 років тому

    lol thank you for your clarification. fortunately, it was not wrong but merely a simplification that I and many others before me have made for the purpose of explaining effective nuclear charge.

  • @sumaia4237
    @sumaia4237 8 років тому +1

    finally I understood the idea of effective nuclear charge,,thanks sir

  • @AKLECTURES
    @AKLECTURES  11 років тому +1

    Thank you. Thats exactly what I was trying to do, glad to hear it worked :)

    • @yandrewww
      @yandrewww 5 років тому

      doesnt the helium have both electrons in same 1s2 orbital. How can we assume there wil be this shielding thing

  • @AKLECTURES
    @AKLECTURES  11 років тому +1

    Thank you! Awesome that it helped :)

  • @neelpatel7571
    @neelpatel7571 10 років тому +2

    a very precise explanation which can be understood by anyone thank you looking forward to more such videos

    • @AKLECTURES
      @AKLECTURES  10 років тому

      neel patel Thanks Neel!

  • @Mathias6191
    @Mathias6191 9 років тому +1

    Thank You, sir. You are an absolute Legend.

    • @AKLECTURES
      @AKLECTURES  9 років тому

      Emile Heskey you're welcome! thanks for watching! :)

  • @PRIYAN57
    @PRIYAN57 9 років тому

    Brilliant! Simply BRILLIANT!

  • @edithperez5237
    @edithperez5237 4 роки тому

    wow this guy is the best teacher

  • @thefinite1966
    @thefinite1966 3 роки тому

    beautifully explained. Great teacher.

  • @ceny021
    @ceny021 12 років тому

    wow. very clearly explained! thanks! i hope you do more tutorials like this!!!

  • @madhukantvashishtha7409
    @madhukantvashishtha7409 9 років тому +1

    sir i'm really very pleased to see your chemisry channal on you tube....
    thanks AK sir

    • @AKLECTURES
      @AKLECTURES  9 років тому

      Madhukant Vashishtha you're very welcome! :-) Thanks for watching.

  • @oshos9
    @oshos9 8 років тому

    Thank You sir........I am glad to find ur channel on UA-cam.....at last....thank you sir

  • @nayralopes4250
    @nayralopes4250 11 років тому

    Thank you a lot for using you time in such a helpful way!
    Your videos really made my day. XD

  • @darrenwhitaker1015
    @darrenwhitaker1015 7 років тому

    excellent explanation! I think I'm finally beginning to understand this subject. Many, many thanks

  • @alexbratchuli5276
    @alexbratchuli5276 12 років тому +1

    Great video. My only question/problem is why did you use helium? In helium, both electrons are in the 1s orbital so shielding doesn't occur. dont they have to be in different sublevels for that to take place? Like in lithium for instance, one of the electrons is in the 2s orbital and is shielded by the 1s electrons.

  • @HelioXPSN
    @HelioXPSN 11 років тому

    If you were my instructor, I would hug the shit outta you. Thanks for the help!

  • @riamukherjee21
    @riamukherjee21 11 років тому

    You are just too awesome! It helped me a lot. I was so confused abt all of this but now it seems simple :D

  • @manobilly1994
    @manobilly1994 12 років тому +1

    hey this actually helped thanks!

  • @AKLECTURES
    @AKLECTURES  11 років тому

    to ease your worry, pretend the electron has been bumped up to the 2s orbital.

  • @edithperez5237
    @edithperez5237 4 роки тому +1

    I need him as my chemistry professor

  • @redsonkabuje5887
    @redsonkabuje5887 6 років тому

    Thank you sir you are using a very precise explanations that are easly undestood

  • @sgasgekar2306
    @sgasgekar2306 10 років тому

    This one was a real help to me! Thanks

    • @AKLECTURES
      @AKLECTURES  10 років тому

      Sanjeev Asgekar You're welcome! :-)

  • @Madeleinebel
    @Madeleinebel 10 років тому +3

    This drawing makes it look as if He has 2 principle energy levels and 1 valance electron, instead of 2 valence electrons in 1principle energy level. Is there a reason you drew it that way? Thanks!

    • @AKLECTURES
      @AKLECTURES  10 років тому +3

      Madeleinebel I did that so that you could differentiate between the two different electrons, so it was simply a matter of convenience. Remember that these two electrons are not found in the same location in space and so its possible that the second electron will be found slightly farther away than the first electron. In fact, according to quantum mechanics, electrons do not actually exist in orbits, like you are taught in general chemistry. But if you stick to the Bohr model description of the atom, then you are absolutely right. The two electrons should be on the same exact energy level. Hope that helped!

  • @vahhabmohammadi8839
    @vahhabmohammadi8839 4 роки тому

    Hi, I am searching for one of your videos that explained the electromagnetic excitation in atoms and the conditions for that. Thanks

  • @polohesse108
    @polohesse108 12 років тому

    The shielding of S orbital electrons is higher due to the fact that the electrons can penetrate the nucleus.

  • @161digvijay
    @161digvijay 11 років тому

    Great one really helped

  • @simunchowdhury9663
    @simunchowdhury9663 11 років тому

    thanks so much this lecture is the best

  • @gandolinamelhem4519
    @gandolinamelhem4519 3 роки тому

    How about comparison of elements in the same group? Zeff should essentially be the same due to the same proton/electron ratio although I've seen that Zeff is presumed to decrease going down a given group. Could you clarify?

  • @justified751
    @justified751 8 років тому

    Thanks sir. This helped a lot.

  • @casillassun1508
    @casillassun1508 11 років тому +1

    Very clear explanation! But I think the falloff of the radii of atoms from left to right in periodic table's row not only depends on the decreasing of the shielding effect,but also the increasing of nucleus right? These two aspects should work together to explain the falloff of those radii. Anyway,your video is very helpful: )

    • @AKLECTURES
      @AKLECTURES  11 років тому +1

      Yes, that is correct. That can be easily seen by examining Coulomb's Law (assuming the electrons and protons at stationary), which states that for a greater quantity of positive charge within the nucleus, the electrons will experience a greater net force. So when the number of protons in the nucleus increases, the greater amount of positive charge pulls those electrons closer, thereby decreasing the radius.

  • @AsutoshSahoo1
    @AsutoshSahoo1 11 років тому +2

    In helium,,both the electrons are in the same shell,,,i.e. the 1st or K shell,,,but you have explained wrong, One in 1st and other in 2nd.

  • @jaafarwamwere6282
    @jaafarwamwere6282 3 роки тому

    Why did you place the 2 electrons of He separately? (had thought is 1s2. ) Thanks

    • @jaafarwamwere6282
      @jaafarwamwere6282 3 роки тому

      I would suggest you use Radial Probability Density. According to RPD, 1s electrons are closer to the nucleus in H than He's 2s ( 2s has 2 nodes, not 2 energy levels). The two electrons are degenerate. Don't put them in different levels.
      Good video though.

  • @YS-rm1em
    @YS-rm1em 10 років тому

    thanks a lot!! ur video really helps it's awesome!!

    • @AKLECTURES
      @AKLECTURES  10 років тому

      You're welcome! Glad to hear it

  • @sokerismylife
    @sokerismylife 11 років тому

    you my nigga. i wish you would be my AP chem teacher. you make it so much more clear

  • @kalpak7368
    @kalpak7368 10 років тому +1

    can you do a video on how to CALCULATE EFFECTIVE NUCLEUR CHARGE for outermost electron

  • @rajukb641
    @rajukb641 11 років тому

    hey its gr8. ionization energy of nitrogen is more than oxygen so does nitrogen has less shielding effect than oxygen?plse answer.

  • @Theharrizable
    @Theharrizable 10 років тому

    How in the He atom, does one electron get pulled away first if they are both in the 1s orbital?

  • @gowergao6312
    @gowergao6312 7 років тому +2

    why does helium own two energy levels instead of one

  • @AKLECTURES
    @AKLECTURES  12 років тому

    ****But lets examine the ionization energies of the two electrons in HELIUM. (not hydrogen)

  • @sidewaysfcs0718
    @sidewaysfcs0718 10 років тому

    shouldn't both electrons in He feel the same force since they are both on the 1s2 orbital?
    aren't they both occupying the exact same energy level? in the seconds chart, Li has 2 electrons on the 1s2 orbital , how come this wasn't the same situation for He's electrons? or was that He atom excited?

    • @AKLECTURES
      @AKLECTURES  10 років тому

      even if helium wasn't excited, the electrons still would not feel the same force because they would not be found at the same location (but to understand this requires quantum mechanics). since we do not want to get into that right now, lets just say we are assuming helium is in its excited state.

  • @playerunknownbattleground8221
    @playerunknownbattleground8221 6 років тому

    thanks pro

  • @junczhang
    @junczhang 8 років тому

    thanks

  • @asmagul6097
    @asmagul6097 12 років тому

    wiil any one tell me taht s orbotal shielding effect is more or d orbital and y??????????????
    howw

  • @abelalonso6658
    @abelalonso6658 6 років тому

    Can you do Hf vs Zr

  • @iti9264
    @iti9264 10 років тому +3

    You move your hands sooo much :p
    Btw great explanation..thnq

    • @AKLECTURES
      @AKLECTURES  10 років тому +1

      Yeah I didn't realize it at first :-P
      Glad you found it helpful.

    • @iti9264
      @iti9264 10 років тому

      :)
      You got some videos on general organic chemistry?

    • @AKLECTURES
      @AKLECTURES  10 років тому

      Do you mean the organic chemistry you cover in an AP chemistry course?

    • @iti9264
      @iti9264 10 років тому

      I don't know about the ap course
      I am from India ..passed class 12 and preparing for mbbs entrance exam

    • @AKLECTURES
      @AKLECTURES  10 років тому

      Oh I see. Well I am not sure but you can check out my website for my organic chemistry lectures. You can find my website in the description.

  • @harshit869
    @harshit869 11 років тому

    Why is f-orbital shielded poorly??

  • @sameerahmedify
    @sameerahmedify 10 років тому

    thank you sir

  • @MuhammadShafiq-jc7rx
    @MuhammadShafiq-jc7rx 2 роки тому

    Respected sir u explain well but He contain on one shell which has two electrons.

  • @riamukherjee21
    @riamukherjee21 11 років тому

    Umm.. Can you explain this as we go down the group? Pleaseee

  • @willy4129
    @willy4129 2 роки тому

    I love you

  • @finback2005
    @finback2005 8 років тому

    mamamia.
    Thanks.

  • @t03040506
    @t03040506 10 років тому

    you save me from tmr's midterm

    • @AKLECTURES
      @AKLECTURES  10 років тому

      Gordon Tan Good luck Gordon! Let me know how it goes :)

    • @t03040506
      @t03040506 10 років тому

      the test was really easy. i over studied it. haha

    • @AKLECTURES
      @AKLECTURES  10 років тому

      lol well thats always the better case scenario! congrats :)

  • @AKLECTURES
    @AKLECTURES  11 років тому

    LOL you're welcome

  • @s13n7ki11l3r
    @s13n7ki11l3r 10 років тому

    but hydrogen has no neutron

    • @AKLECTURES
      @AKLECTURES  10 років тому

      sometimes it does... ;-)

  • @rohil7898
    @rohil7898 7 років тому

    hydrogen has only 1 proton bro!!!!! wtf

  • @dadathegreat6496
    @dadathegreat6496 4 роки тому

    Gana angrez na bane

  • @bl2504
    @bl2504 6 років тому

    can you speak faster? this is way too slow...sorry