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Technique I Use of Spectrophotometer_1_1_1

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    305636
  • Technique I:  Use of Spectrophotometer 

     

    Section 1:  Purpose of Technique 

     

    This technique describes how to use a laboratory spectrophotometer.   

     

    Section 2: Operations of Spectronic 200E   

     

    There are several types of spectrophotometers that are used to determine the amount of light absorbed within a given sample solution. The spectrophotometers used in the lab are the Spectronic 20, Spectronic 20+ and Spectronic 200. Before using the Spectronic 200, follow these steps to make sure that no damage or injury will occur due to faulty or careless behavior. 

     

    NOTE:  Several terms are used for the container used to hold a sample in a spectrometer.  This procedure will use the term ‘optical cell’ but other terms like ‘cuvette’ may be used in reference texts and instrument manuals.      

     

    1. Make sure the spectrophotometer is on a stable, flat surface free from vibrations.  

     

    1. Plug in the spectrophotometer and turn it on by flipping the power switch at the back of the machine. The following image will appear on the screen when it is on. (Figure 1) 

     

    C:\Users\ecastaneda767\Downloads\20190722_144012_Film1.jpg 

    Figure 1. On screen 

     

    1. Make sure that the sample compartment is empty. Then, press ENTER. The following image will appear on the screen. (Figure 2)  

     

    C:\Users\ecastaneda767\Downloads\20190722_144015_Film1.jpg 

    Figure 2 

     

    1. Look at the image below. Once at this point, wait for approximately 1 minute.  

     

    1. The screen will then display the Home Menu. Use the arrows to select the SPEC 200E MODERN INTERFACE option, then press ENTER. (Figure 3) 

     

    C:\Users\ecastaneda767\Downloads\20190722_144116_Film1.jpg 

    Figure 3. SPEC 200E MODERN INTERFACE 

     

    1. The screen will then show APPLICATION LIVE DISPLAY. Press the right arrow. (Figure 4)  

     

    C:\Users\ecastaneda767\Downloads\20190722_144124_Film1.jpg 

    Figure 4. APPLICATION LIVE DISPLAY 

     

    1. The screen will then show APPLICATION MULTI λ, press the right arrow again. (Figure 5)  

    C:\Users\ecastaneda767\Downloads\20190722_144128_Film1.jpg 

    Figure 5. APPLICATION MULTI λ 

     

     

     

     

    1. Then the screen will show APPLICATION QUANT, press the right arrow again. Refer to figure 6.  

    C:\Users\ecastaneda767\Downloads\20190722_144132_Film1.jpg 

    Figure 6. APPLICATION QUANT 

     

    1. Then the screen will show APPLICATION ANALYZER, press the right arrow again. Refer to figure 7.  

    C:\Users\ecastaneda767\Downloads\20190722_144136_Film1.jpg 

    Figure 7. APPLICATION ANALYZER 

     

    1. Then the screen will show APPLICATION SCAN, press ENTER. Refer to figure 8.  

     

    C:\Users\ecastaneda767\Downloads\20190722_144200_Film1.jpg 

    Figure 8. APPLICATION SCAN 

     

    1. Fill an optical cell half-way with laboratory water. Use Light-Duty Tissue Wipers, to wipe off any fingerprints on the outside of the cell. 

     

    1. Place the optical cell into the sample compartment, then press the AUTOZERO KEY.  

     

    1. After the spectrophotometer is done zeroing, replace the optical cell filled with water with an optical cell filled with your chemical sample. 

     

    1. Wipe the optical cell with the Light-Duty Tissue Wipers and place it into the sample compartment. Press ENTER.  

     

    1. After the spectrophotometer is done analyzing the sample, a graph will appear to the right of the screen.  

     

    1. Use the right arrow to move cursor to the peak of the curve. This will show the peak absorption.  

     

    1. Press the HOME KEY when you are done. To turn the spectrophotometer off, flip the power switch on the back of the machine.