ch_07_skeleton%20notes - Chapter 7 Periodic Properties of...

Info icon This preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
Chapter 7. Periodic Properties of the Elements 7.1 Development of the Periodic Table The periodic table is the most significant tool that chemists use for organizing and recalling chemical facts. Elements in the same column contain the same number of ________________________________. How do we organize the different elements in a meaningful way that will allow us to make predictions about undiscovered elements? The periodic table arises from the periodic patterns in the electronic configurations of the elements. In the first attempt Mendeleev and Meyer arranged the elements in order of increasing atomic weight. 7.2 Effective Nuclear Charge Effective nuclear charge ( Z eff ) is the charge experienced by an electron on a many-electron atom. The effective nuclear charge is not the same as the charge on the nucleus because of the effect of the inner electrons. The electron is attracted to the nucleus, but repelled by electrons that shield or screen it from the full nuclear charge. The nuclear charge experienced by an electron depends on its distance from the nucleus and the number of electrons in the spherical volume out to the electron in question.
Image of page 1

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

View Full Document Right Arrow Icon
Periodic Properties of the Elements 79 As the average number of screening electrons ( S ) increases, the effective nuclear charge ( Z eff ) decreases. As the distance from the nucleus increases, S increases and Z eff decreases. 7.3 Sizes of Atoms and Ions Consider a collection of argon atoms in the gas phase. Now consider a simple diatomic molecule. Periodic Trends in Atomic Radii Atomic size varies consistently through the periodic table.
Image of page 2
Chapter 7 80 Periodic Trends in Ionic Radii Ionic size is important: Just as atomic size is periodic, ionic size is also periodic.
Image of page 3

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

View Full Document Right Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

{[ 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