In this lab activity, you will be using the spreadsheet to calculate the energy levels, frequencies, and wavelengths of electrons in orbits. The question is: how can we observe transitions (movement) of electrons from an excited state to a ground state? We are also interested in knowing: which series can we see?
Atoms can absorb energy through their electron structures in the form of energy packet (or "quanta") called a photon. When this energy packet is absorbed, the electron in orbit around the nucleus move to a higher (more distant) level. This level is called the excited state. Naturally, the electron cannot remain at this excited state for a very long time (it stays there for about 10-8 seconds, or for .00000001 seconds). When the electron "falls" back to the ground state level, energy is released. Depending on the wavelength of this fall, you might be able to see the energy released in the form of color (ie, a burst of light). Any energy with a wavelength between 380 and 750 nanometers (nm) will be visible to most people.
Your objective in this lab is to create a spreadsheet that will allow you to calculate the change in energy, the frequency, and the wavelength when an electron moves from an excited state to a ground state. You will be asked to use the full electromagnetic spectrum to predict which part of the spectrum appears for several different energy levels.
The equations you will need to model are as follows:
where RHis the Rydberg constant, with a value of 2.18 x 10-18 J.
where h is Planck's constant, with a value of 6.63 x 10-34
where c is the speed of light, with a value of 3.00 x 108 meters per second (m/s). Don't forget to convert this to nanometers per second!
Wavelength Range (nm) | Radiation Produced |
Less than 185 | X-rays |
185-380 | Ultraviolet |
380-450 | Violet |
450-495 | Blue |
495-550 | Green |
550-570 | Yellow-Green |
570-590 | Yellow |
590-620 | Orange |
620-750 | Red |
750-1900 | Near Infrared |
1900-2500 | Infrared |
Above 2500 | Microwaves, radiowaves |
Hint: use the "fill" command to save yourself typing! Work smarter, not harder.
To Slides:[1]
[2]
[3]
[4]
[5]
[6]
[7]
[8]
[9]
[10]
[11]
[12]
[13]
[14]
[15]
[16]
[17]
[18]
[19]
[20]
[21]
[22]
[23]
[24]
[25]
[26]
[27]
[28]
[29]
[30]
[31]
[32]
[33]
[34]