Experiment on Spectrophotometer

Method

Refer to manual

Results

(Nm)                (ABS)

380                0.285

385                0.307

390                0.380

395                0.479

400                0.608

405                0.681

410                0.606

415                0.423

420                0.255

The table above shows the results for the determination of peak wavelength.

Tube No.                                        1        2        3        4        5        6

Stock Solution (0.1mg/ml) (ml)                0        2        4        6        8        

Deionized Water (ml)                                10        8        6        4        2        0

Final Concentration [cytc] (mg/ml)                0        0.02        0.04        0.06        0.08        1

ABS at peak    = 405 nm                        0        0.012        0.220        0.281        0.649        0.661

Corrected ABS (-blank)                        0        0.012        0.220        0.281        0.649        0.661

The above information shows the results of the Stock Cytc Solution 0.1 mg/ml.

The determination of Unknown Cyt C Concentration.

                ABS of Unknown = 0.410 ABS Units

                Concentration from Graph =

The Sources Of error

 0.02 = 4 %

 0.410

Mass Structure of Cytochrome C 13,300 ÷ 0.1 = 7.5 X 10-6   m

Cytochrome C 12500 x 1 = 0.938

                7.5 x 10-6

Purity of Cytochrome c: 0.661 x 100 = 70.46 %

                             0.938

Conclusion

The aim of the experiment was to determine the light absorbed by the solution, hence it was achieved as the results show the amount of absorption at different wavelength, the peak absorption shows me that there is a rise in absorption until it hits the peak at 405 nm, and then there is a sudden drop in absorption.

The results of the calibration of cytochrome c show me that it goes up by each test tube, as more ml of stock solution is used. However, the results should show on the graph as a straight line, in this case there must have been an error or the solution was not prepared and measured correctly. The sources of error show a 4%. Overall the experiment was a success as the objectives were met and the absorption of the known solution were recorded.