Journal Entry:

What is the structure of an atom? What affects the structure of an atom?

Learning Intentions

• You learn what affects atomic structure.

• You will learn why the classical shell model of an atom has been refined to the quantum mechanical model using data from line spectra, and ionization energy.

• You will learn how to determine and write out the electron configurations for an atom of a particular element.

• You will be able to use an element's position on the periodic table to determine the electron configuration for an atom using the Aufbau principle.

Closing Task:

You can write the electron configuration for an element.

Content Standards being covered:

The atom is composed of negatively charged electrons, which can leave the atom, and a positively charged nucleus that is made of protons and neutrons. The attraction of the electrons to the nucleus is the basis of the structure of the atom. Coulomb's law is qualitatively useful for understanding the structure of the atom. (EK 1.B.1)

As is the case with all scientific models, any model of the atom is subject to refinement and change in response to new experimental results. In that sense, an atomic model is not regarded as an exact description of the atom, but rather a theoretical construct that fits a set of experimental data.  (EK 1.D.1)

The currently accepted best model of the atom is based on the quantum mechanical model. (EK 1.C.2)

The interaction of electromagnetic waves or light with matter is a powerful means to probe the structure of atoms and molecules and to measure their concentration. (EK 1.D.3)