Imagine you are in a lab with a set of pipettes, a tube of bromophenol blue, and lots of tubes into which you can make your dilutions. You also have a spectrophotometer, so you can measure the absorbance of all the dilutions of the bromophenol blue solution (BPB).
Part A)If you have a tube of 0.2% BPB solution, how would you make 3 m1 of a 0.1% BPB solution? What is the dilution factor of 1% compared to the original 2% stock?
Part B) Plan how you would prepare the following straight dilutions of the 0.1% BPB solution: 1:2, 1:4, 1:5, 1:10, 1:50,and 1:100. The ?nal volume of each dilution should be 4 ml. In your plan, you should also indicate the ?nal % BPB ineach dilution. Volume BPB Volume Water Final % BPB
Part C) If we were in the lab, you would not use the spectrophotometer to measure the absorbance of each dilution you made at a wavelength of 590 nm. The more dilute the sample is, the lower the absorbance. Does that make sense to you, if so, why?