User:Jason O Archer/Notebook/PHYC 307L Junior Lab/2008/11/16
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Balmer Series Lab 11/16/08
The exponential calibration curve we obtained from Excel is as follows:
λ' = 400 + 1.0667*(λ - 400)0.9853, where
(This curve had an R2 value of 1 in Excel; the polynomial curves had lower values, so we used the exponential curve. We also chose the exponential curve since the error seemed to grow very fast with the increase in value very sharply.)
Note: The shifts of 400 came from an attempt to get the best possible fit for the exponential curve by having a starting point close to the origin.
From this curve, we can calculate the wavelengths measured for regular hydrogen and deuterium to be as follows:
From the equation λ-1 = R(2-2 - n-2), where
we can make calculations for the Rydberg constant. From calculation in Excel, we obtain the following eight values (in 1/m):
The average value we calculate is 10964446.07 ± 7548.89 1/m. (mean ± SEM).
Since the official value is given as 10967758 1/m, we calculate the percent error to be an astonishingly low 0.0302%.
The Rydberg constant for hyrdogen is 10967758 1/m, as we are given. The Rydberg constant for deuterium, by the formula R = μe4/8ε02ch3, where
we can calculate R to be 11055173 1/m for deuterium; this is a low 0.7970% difference.