Atomic Emission Spectra Questions

Name: _________________________________ Section Number: _________

Watch the Video: https://www.youtube.com/watch?v=BgNzEERlBf4

Fill in the tables with 4 significant figures and answer the following questions and make sure you show your work for ALL calculations.

Table 1. Silicon Metal

 Wavelength (nm) Frequency (Hz) Energy (J) Light color or Radiation 100 300 (max) _______

Calculations:

Table 2. Different Metals

 Metal Max. Wavelength (nm) Frequency (Hz) Energy (J) Germanium Tin Lead

Calculations:

What do your results for silicon, germanium, tin, and lead indicate? The energy you calculated for the maximum wavelength represents the minimum energy required to eject an electron. Is there any trend? Consider the position of these elements in the periodic table and what ejecting an electron from an atom represents?

Table 3. Hydrogen emission

 Line Number: Wavelength (nm) Frequency (Hz) Energy (J) Line #1 (Left) 410 Line #2 434 Line #3 487 Line #4 (Right) 656

Calculations:

The four lines you see in the visible region for the atomic emission spectrum of hydrogen are the so called Balmer series. They are due to electron transitions from atomic energy n=6 to n=2, n=5 to n=2, n=4 to n=2, and n=3 to n=2.

Table 4. Balmer Series for hydrogen

 Transition Energy Difference (J) Wavelength (nm) Color n=3 to n=2 n=4 to n=2 n=5 to n=2 n=6 to n=2

Calculations:

What is the difference between the emission spectra of the molecules and those of the elements you observed in the video? Why do you think the emission spectra of the elements and molecules are so different?