PHYS222_Lab11

.pdf

School

The University of Tennessee, Knoxville *

*We aren’t endorsed by this school

Course

222

Subject

Chemistry

Date

Dec 6, 2023

Type

pdf

Pages

Uploaded by CoachTeam14761

Name: Taylor Totorp Email: ttotorp@vols.utk.edu Laboratory 10 Report Goal: This lab focuses on how atomic spectra and lasers work and can be made in the Balmer series of hydrogen and with an He-Ne laser Experiment 1: • The experimental plot R value is 0.01095 nm -1 , and the calculated value for R is 0.01097 nm -1 . (Calculation: R=13.6/1240 = 0.01097) • These values are extremely close to each other the percent difference being 0.1824%. (Calculation: % Diff = (0.01097-0.01905) / [(0.01097-0.01905)/2] = 0.001824*100 = 0.1824%) • I understood how this experiment was to test how our accuracy within the experiment. 1/λ= R(1/4 - 1/n i 2 ) is the known equation, so to prove the Rydberg constant that equation tells us that R=(1/λ) / (1/4 - 1/n i 2 ). Exploration 1: • The He-Ne spectrum given in the lab contains lines from both He and Ne as can be seen when comparing how the He-Ne spectrum has lines from both the He spectrum and Ne spectrum. • The strength of some of the lines depends on the gas mixture. For example at around 670 nm both the Ne and He show signals, so on the Ne-He spectrum the strength of the signal is stronger than both were individually. • The laser line is not a prominent line initially the Ne spectrum. y = 1.095E-02x 0 0.0005 0.001 0.0015 0.002 0.0025 0.003 0 0.05 0.1 0.15 0.2 0.25 1/λ (nm -1 ) (1/4 - 1/ni2) 1/λ Versus (1/4 - 1/ni2)

Exploration 2: Two-Level Atom: • When optically pumping an atom at the preset wavelength and medium lamp control level, there can be simulated emissions observed. This can be seen as the photons come into contact with the level 2 pumping scheme the number of photons emitted increases. • At the preset wavelength and a low-level lamp control, the number of photons emitted is much slower. • At the preset wavelength and a high-level lamp control, the number of photons emitted is much higher and almost constant. • When the lifetime of the atom is decreased, the emissions slow until at the smallest lifetime of the atom there are no more emissions. • As the wavelength changes outside the red color zone, the emissions completely stop. Three-Level Atom: • When pumping the three-level atom with the blue lamp, the photons are emitting red regularly and in all directions. • When showing the “display photons emitted from the upper state”, the photons now seen are showing in multiples of 2 blue photons also going in all directions and smaller dark red stars going in all directions • When changing the lifetime of the upper and lower states they have the same reactions, the lower state has more emissions and energy the higher the lifetime, and less emission and energy the lower the lifetime. Build a Laser: • Firstly, the laser needs three energy levels. • Then, the laser needs to be pumping the second energy level. • The laser’s third energy level needs to me metastable. • Changing the wavelength and energy level decreases the ease of achieving a population inversion. • To build a laser you need mirrors, and one needs to be highly reflective and the other be not reflective. • You can blow up your laser if there is too much heat over time. Reflection: Lab 1 focuses on how atomic spectra lasers and lasers can be analyzed and built. Experiment 1 centered around the Balmer series of hydrogen in order to prove the accuracy of our experimentation by confirming the value of the Rydberg constant (R). The experimental R value followed what was expected with a value of 0.01095 that was 0.1824% different from the known value. Exploration 1 dove into looking at the He-Ne laser and comparing the laser light and Ne- He spectra to the individual Ne spectra and He spectra. This exploration concluded that the He-

Your preview ends here

Eager to read complete document? Join bartleby learn and gain access to the full version