Atomic Structure and Periodicity

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Increase going down a group, because of the increase in orbital sizes in successive principal quantum levels.

Slide 50

The Radius of an Atom

Slide 51

Atomic Radii for Selected Atoms

Slide 52

Information Contained in the Periodic Table

1. Each group member has the same valence electron configuration. Group elements exhibit similar chemical properties.

2. The electron configuration of any representative element can be obtained from periodic table. Transition metals – two exceptions, chromium and copper.

Certain groups have special names (alkali metals, halogens, etc).

Metals and nonmetals are characterized by their chemical and physical properties. Many elements along the division line exhibit both metallic and non metallic properties which are called metalloids or semimetals.

Slide 53

Special Names for Groups in the Periodic Table

Slide 54

Summary

Electromagnetic Radiation: Wavelength like behavior.

Frequency,  = c/ ( = wavelength, c = speed of light).

Energy Transfer, E = h = hc/

de Broglie’s Equation:  = h/m

The Bohr Model: electron in a hydrogen atom moves around the nucleus only in certain allowed circular orbits.

Quantum Mechanics: H= E

Heisenberg Uncertainty Principle: Position and momentum cannot be determined precisely at a given time.

Slide 55

Quantum Numbers: Principal QN, Angular momentum QN, Magnetic QN, an Electron Spin QN.

Orbital Shapes and Energies: s, p, and d orbitals.

Pauli Exclusion Principle:

Aufbau Principle:

Hund’s Rule:

Periodic Table:

Ionization Energy:

Electron Affinity:

Periodic Trends: