• AMA with Certified Student Loan Professional

    Join SDN on December 7th at 6:00 PM Eastern as we host Andrew Paulson of StudentLoanAdvice.com for an AMA webinar. He'll be answering your questions about how to best manage your student loans. Register now!

Shielding Effect

happyana

Full Member
10+ Year Member
Aug 31, 2007
140
0
  1. Other Health Professions Student
    Can someone explain what happens when going across/up/down on the periodic table for the shielding effect? I know that it remains constant going down, but what about going towards the right or left?
     

    Albuterol

    Full Member
    10+ Year Member
    7+ Year Member
    Dec 14, 2007
    1,190
    0
    North Jersey
    1. Resident [Any Field]
      shielding increases as u go across a period from left to right.
      this is because electrons are added but the core shell stays the same. The Zeff increases and the radii of the atom decreases because the valence electrons are more tightly bound.

      going down a group the shells increase in size but the Zeff stays the same and this is related to the increase in atomic radii. going up the shells decrease and the radii becomes smaller.

      Zeff- for Na has 11 electrons. in the row before it the core electrons are 10.
      11-10= + 1, so Na valence electrons feel a +1 shielding effect.

      Zeff- for Mg has 12 electrons. in the row before it the core electrons are 10.
      12-10= +2, so Mg valence electrons feel a +2 shielding effect.

      hope this helps.
       
      About the Ads
      This thread is more than 13 years old.

      Your message may be considered spam for the following reasons:

      1. Your new thread title is very short, and likely is unhelpful.
      2. Your reply is very short and likely does not add anything to the thread.
      3. Your reply is very long and likely does not add anything to the thread.
      4. It is very likely that it does not need any further discussion and thus bumping it serves no purpose.
      5. Your message is mostly quotes or spoilers.
      6. Your reply has occurred very quickly after a previous reply and likely does not add anything to the thread.
      7. This thread is locked.