Full Lab Manual
Introduction & Goals
Chemistry & Background
In Your Write-up
In the first part of this experiment you will use a meterstick spectroscope to determine the wavelengths of visible light emitted by a hydrogen atom. The wavelengths of the emitted photons will be converted to photon energies which will then be used to identify the change in atomic energy level which gave rise to the emitted photon. The Bohr model will be used to provide the required expressions for the allowed discrete energy levels for a one-electron atom. In the second part of the experiment, you will observe the spectrum of the sodium atom in the same way. From the measured spectrum and the ground state sodium atom ionization energy you will be able to calculate the effective nuclear charge for a 3s and a 3p electron in the sodium atom. Finally, you will compare qualitatively the spectra of a series of elements and the light emitted by a fluorescent lamp.
Why are atomic spectra composed of light emitted in discrete lines, rather than continuous bands?
How are the energy of the light emitted and the energy of the electron in the atom related?
How are single- and multi-electron atoms different? What do the electron energies depend on, in each case?
What is effective nuclear charge? Why is it different for a sodium electron in a 3p orbital and a 3s orbital?
Why do different elements have different spectra?
How do fluorescent lights work? What element do they contain?
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