Explains how you calculate concentrations when you have two components that absorb in similar wavelengths. This video assumes you know about Beer's Law. If not, you may want to watch this video: • Absorbance & Emissions...
How can I estimate the concentration of substance A and substance B in the mixture when the info given: absorbance at the same 2 wavelengths for and B, A concentration and B concentration are the same, absorbance of mixture?? It was on paper based exam, no access to excel whatsoever xx
@@Double0piI have tried to follow the steps and I am not sure where do I make mistake, my concentrations come up negative 😭. Absorbance at 238nm- Phenobarbital 0.551, Oxycodone 0.477, Unknown 0.652 At 280nm- Phenobarbital 0.07, Oxycodone 0.05, Unknown 0.493. Both samples Phenobarbital and Oxycodone are at 5.20x10^-5 M concentration. The molar abs that I calculated ( molar abs= A/C ) are at 280nm- Phenobarbital 1346, Oxycodone 962. At 238nm- Phenobarbital 10596, Oxycodone 9173. step 1 result: 0.652-9173 Coxycodone/ 10596= Cpheno step 2) 0.493= 1346 (0.652- 9173 Coxy/ 10596) + 962 Coxy Step 3) 0.493= 0.0828- 1165 Coxy + 962 Coxy 0.4102= -203 Coxy Coxy= -0.002 Step 4) 0.652- 9173 (-0.002)/ 10596= Cpheno Cpheno= -17.694/ 10596= -0.00167 😭😭😭
It's just an example. You can do this for literally any set of two wavelengths. Heck, you can do it for three if you are willing to wrestle with the math.
