1. Atomic Emission
General Chemistry 101/102 Laboratory Manual University of North Carolina at Wilmington

2. Atomic Emission Purpose Safety Considerations
To use a simple spectroscope to observe the emission spectra of selected elements.
To calculate the frequency and energy of photons observed in the emission spectra of lithium, sodium, and copper.
Safety Considerations
The flame emission apparatus should be used only in the hood.
Immediately cleanup any spilled solutions.

3. Atomic Emission Procedure
Use the spectroscope to observe the prominent lines in the spectrum of a fluorescent lamp.
point slot at light source
view here
spectroscope (Boreal, Inc.)
spectrum of fluorescent lamp
450 nm
570 nm

4. Atomic Emission Procedure
Observe the flame emission spectra for Na, Li, and Cu and record the wavelength of the prominent spectral line for each element. Na Li Cu

5. Atomic Emission Calculations c = l n n = l c = = E = h n
570 nm
Calculations
c = l n
n = l c =
3.00 x 108 ms-1
570 x 10-9 m
5.26 x 1014 s-1 =
E = h n
photon
= (6.63 x J·s) (5.26 x 1014 s-1)
= x J
photon
(3.49 x J) (6.02 x 1023 photon)
photon
mol
E =
mol
= x 105 J/mol
E = 210 kJ/mol
mol