12. Atomic structure

12. Atomic structure

12.1 Electrons in atoms

Nature of science:

• Experimental evidence to support theories - emission spectra provide evidence for the existence of energy levels.

Understandings:

• In an emission spectrum, the limit of convergence at higher frequency corresponds to the first ionization energy.

• Trends in first ionization energy across periods account for the existence of main energy levels and sub-levels in atoms.

• Successive ionization energy data for an element give information that shows relations to electron configurations.

Applications and skills:

• Solving problems using E=hv.

• Calculation of the value of the first ionization energy from spectral data which gives the wavelength or frequency of the convergence limit.

• Deduction of the group of an element from its successive ionization energy data.

• Explanation of the trends and discontinuities in first ionization energy across a period.