The absorption spectrum of methyl orange
Aim
To prove beer lamberts law
Introduction
This experiment is to prove Beer lamberts law, which states that absorbance is proportional to concentration.
Part one materials 1. Colorimeter 2. Methyl orange 3. Potassium permangate 4. Cuvette 5. Deionised water
Part one methods 1. Rinse one cuvette with deionised water 2. Fill one cuvette with deionised water and “zero” the colorimeter machine 3. Fill the cuvette that was rinsed with 4ppm Methyl orange 4. Record the absorbance values for 4ppm Methyl orange, making sure to zero the machine with the deionised water cuvette after each reading is taken. 5. Repeat step 4 with 6ppm Methyl orange 6. Repeat steps 4 & 5 for potassium permanganate 4ppm & 6ppm 7. Record all your results in individual tables
Part One Results
Methyl Orange Absorbance | 4ppm | 6ppm | 440 | .12 | .18 | 470 | .13 | .12 | 490 | .07 | .10 | 520 | .00 | .04 | 550 | .02 | .03 | 580 | .04 | .02 | 590 | .03 | .01 | 680 | .05 | .01 |
Part One Results
Potassium Permanganate Absorbance | 4ppm | 6ppm | 440 | .02 | .03 | 470 | .01 | .03 | 490 | .02 | .05 | 520 | .05 | .10 | 550 | .04 | .08 | 580 | .04 | .00 | 590 | .05 | .02 | 680 | .01 | .01 |
Part two materials 1. Colorimeter 2. Methyl orange 3. Cuvette 4. Unknown solution 5. 10ml Pipette 6. Pipette Filler 7. 50ml Volumetric flask × 4
Part two Method 1. Using a Methyl orange solution of 40ppm prepare 4 volumetric flasks containing methyl orange 2ppm, 4ppm, 6ppm, 8ppm. 2. To do this I used a pipette filler and pipette to measure out the amount of methyl orange I needed . 2.5mls = 2ppm, 5.0mls = 4ppm, 7.5mls = 6ppm & 10mls = 8ppm 3. After I measured out my methyl orange I diluted each with deionised water up to the calibration mark on the volumetric flask. 4. I then poured each solution into separate