Unit1_Chap12_SUM08Zumdhal-4 - The Aufbau Principle and the...

Info icon This preview shows pages 1–3. Sign up to view the full content.

The Aufbau Principle and the Periodic Table We can have n 2 atomic orbitals/principal energy level. Since two electrons can occupy one orbital, we can have a maximum of 2n 2 electrons/principal energy level. 1- Aufbau Principle: When writing electron configuration, electrons are added to the lowest energy level. n = 5 s p d f n = 4 s p d f n = 3 s p d n = 2 s p n = 1 s 2- Hund’s Rule: Electrons occupy all orbitals in a sublevel of energy before pairing begins. These unpaired electrons must have parallel spins. 3- Pauli Exclusion Principle: No two electrons in an atom can have the same four quantum numbers (2 electrons occupying the same orbital must have opposite spin). Paramagnetism and Diamagnetism Paramagnetism: Weak attraction toward a magnetic field. It is due to the presence of unpaired electrons. Diamagnetism: Weak repulsion by a magnetic field. It occurs when all the electrons are paired.
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

POLYELECTRONIC ATOMS How can the quantum mechanical model of the hydrogen atom be extrapolated to account for polyelectronic atoms?
Image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.
  • Fall '09
  • Atom, Electrons, Zeff

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern