Spectroscopy Lab Report

cName Nicholas CasselGen Chem 1210 23 March 2013 Blinded By the unhorse Abstract In this experiment we were provided a cereal cuff spectrometer to watch the expelling grooves of noble gases and total heat. establish on the master readings on the spectrometer and the Balmer- rydberg formula, their wavelengths and per centum fault were fitted to be extrapolated. Based on the literature catch, the cereal box spectrometer proved its value as a decently accurate spectrometer. door Every element and subsequent subatomic particle associated emits uncontaminating in like manner know as electromagnetic radiation, when in an excited state.Analyzing this emitted b basebornzy rat give insight to the constitution and characteristics of them. The watery given off by an energetic every(prenominal)y excited atom is non a continuous distribution of all practicable wavelengths, but rather consists of a few wavelengths giving a series of separate lines. Spectroscopy is the anal ysis of that emitted light-headed and its dispersion into to its divisor wavelengths and colors. Niels Bohr explained the discrete spectrum of henry? by relating it to the electron. Normally the electron in the hydrogen atom is fit(p) in the first brawniness-level.When a hydrogen atom atoms gains ability, the electron moves from a level energy-level to one of highschooler energy. The energy gained by the atom is particularly the sum up of energy needed to move the electron from the abase energy-level to the higher energy-level. With its electron in a higher energy-level, the atom is now in an uns put back, higher energy, excited state. The tendency is for electrons to divert the lowest level available. So short after gaining the energy, the electron returns to a pull down energy-level. Energy must be given up when this occurs, and the energy is lost as light.Each line in the emitted light of hydrogen represents the movement of an electron from a special(prenominal) outer level to a particular proposition inner one. We judge this emitted light against the electromagnetic spectrum with a spectrometer. A spectrometer is an cats-paw that gathers light particles (photons) and is able to determine the chemic make-up of the source. A spectrometer breaks up a beam of light into its component colors. Usually it single-valued functions a prism or a diffraction grating. Light goes in as a beam of white light and is split into a rainbow. Particular atoms become light at particular frequencies (colors) and so outhouse be identified in the lab.The electromagnetic spectrum is the range of all possible wavelengths of electromagnetic radiation. This range extends from sub-radio waves to gamma rays. distinct light falls within this spectrum. The light emitted by each(prenominal) element is independently different and has different colors that can be involven on the spectrum. The Balmer-Rydberg formula is utilise to describe the outpouring lines of hy drogen crosswise the entire spectrum and not just berthable light. The purpose of this laboratory experiment is to see the emitted wavelengths of elements through a spectroscope and view the wavelengths with the Balmer-Rydberg formula.Then with the calculations, relate them to the atom. I believe that with the manufacture calculations and comparisons the wavelengths, each waiver line lead be able to be goaded. data-based The procedures as per the lab manual scalawagboy 258 (Grossie, underwood, 2012) were to first calibrate our spectroscope with helium. looking at helium through the spectroscope, the emission lines where seen and recorded. That data was and wherefore put into Microsoft exceed and put into a graph. From the graph a formula was extrapolated. The spectroscope was used to bring out and record the fours spectral lines of hydrogen.The standardisation eyepatch from helium determine the wavelengths of each of the lines by extrapolation. Comparing the deliber ate wavelengths to those determined from the calibration plot, and then calculate the percent delusion for the values. Then the spectroscope was used to view the spectral lines of argon, krypton, neon and Xenon. These noble gasses ar then calculated in the said(prenominal) manner as hydrogen. Data Results The wavelengths (? ) for helium for the calibration were given to us in our lab manual on page 261 (Grossie, D. , et al. 2012). With the spectroscope, the helium in the discharge tube-shaped structure was detect. The emission line home plate eading and colors were then recorded on defer 1. 1 which can be arrange below. These values where then put into an surmount spreadsheet and graph was formed (mesa 1. 2). An equation was then extrapolated from the data that would give the data-based wavelength (expt ? ) values that will be used for later(prenominal) values. The rationalise line for table 1. 2 was established to see the relationship amongst wavelength and scale reading s. Expt ? =a ? +b Expt ? =7. 1541 ? + 343. 12 circuit board 1. 1 atomic number 2 calibration ? (nm) shield adaptation Color 667. 8 45 cherry- bolshie 587. 6 35 Yellow 501. 6 22 greens 492. 2 20 unconsecrated-green 471. 3 18 Blue 47. 1 15 Violet knock back 1. 2 Helium Calibration Graph Then, by standard and calculating the emission lines in the hydrogen line spectrum, the data on table 1. 3 was collected. The calculated wavelength (Calc ? ) was determined by the Balmer-Rydberg formula. 1? =R(1m2-1n2) R=Rydberg ageless=1. 0968x107m-1 The percent break was then calculated by the following equation. defect %=(calc ? -expt ? )calc ? The experimental wavelength (expt ? ) was determined with, Expt ? =7. 1541 ? + 343. 12 TABLE 1. 3 Hydrogen Emission subdue Reading Color Expt ? m n Calc ? ? % misconduct 1 2 1 3 1 4 45 Red 665. 05 2 3 656. 11 1. 36 26 green 529. 12 2 4 486 8. 87 13 Blue 436. 12 2 5 433. 94 0. 5 29 Indigo 550. 58 2 6 410. 07 34. 26 3 4 3 5 3 6 The measuring and calculating of the emission lines in the Neon, Argon, Krypton and Xenon line spectrums yielded the data on tables 1. 4-1. 7. The calculated wavelength (Calc ? ) was determined by the Balmer-Rydberg formula. 1? =R(1m2-1n2) R=Rydberg Constant=1. 0968x107m-1 The percent erroneousness was then calculated by the following equation. error %=(calc ? -expt ? )calc ?The experimental wavelength (expt ? ) was determined with, Expt ? =7. 1541 ? + 343. 12 TABLE 1. 4 Neon Emission Ne Scale Reading Color Expt ? Calc ? % error 45 Red 665. 05 640. 2 3. 88 38 Orange 614. 97 607. 4 1. 24 35 Yellow 593. 51 588. 2 0. 9 27 Green 536. 28 540. 1 0. 7 TABLE 1. 5 Argon Emission Ar Scale Reading Color Expt ? Calc ? % error 10 Violet 414. 66 454. 6 8. 78 32 Yellow 572. 05 514. 5 11. 18 54 Red 729. 44 528. 7 37. 96 TABLE 1. 6 Krypton Emission Kr Scale Reading Color Expt ? Calc ? % error 30 Green 557. 74 476. 3 17. 09 13 Violet 436. 12 406. 7. 31 15 Blue Violet 450. 43 415 . 4 8. 43 34 Yellow 586. 35 520. 8 12. 58 TABLE 1. 7 Xenon Emission Xe Scale Reading Color Expt ? Calc ? % error 21 Green 493. 35 513. 1 3. 84 18 Blue 471. 89 464. 3 1. 63 Discussion The helium trend line in table 1. 2 shows that as the interminable the wavelength gets, higher the scale rating becomes. This is because the longer the wavelength is, the less energy it has. The emission lines of hydrogen were then observed and recorded on table 1. 3 with the scale readings. The m and n levels were already given to us on the table prior to the beginning of the lab. apply the Balmer-Rydberg formula, the wavelength could be calculated. Using the calibration of helium, the experimental calculation was able to be determined with the equation extrapolated from excel. The dickens results gave rise to the error calculations. Comparing the hydrogen results with tables 1. 4 1. 7, its can be seen that in that respect is a trend of the longer the wavelength is, the more than percent error there is. by our cereal box spectrometers, the emission lines of the low energy waves viewed a the color red are more broad than that of the high energy waves because theirs are much longer respectively.This makes it more difficult to determine the exact scale reading. With the correct calculations as proposed, each emission line was able to be determined. Conclusion The ability to observe emission lines then decipher the element is a useful application in the field of astronomy. Astronomers are able to view the emissions and determine the chemical make up of a specific object billions of miles away. The data collected indicated that as the lower the energy of the waves, there was a error percentage. This error is in any case from a cereal box spectrometer.It can be inferred that there is an inherent amount of decreased precision in assessing the scale readings. Future experiments could still make use of the cereal box but also have a laboratory tonus spectrometer to compare accu racy too. there could be significant human error in the construction of the cereal box versions. The results of this experiment, bar any inaccuracy, where still in line of the calibrated helium. References Grossie, D. & Underwood K. (2011). Laboratory Guide for Chemistry. Atomic spectroscopic analysis, Wright State University. Dayton, OH.