# Beer's Law

## No, not that kind of beer...

The Beer-Lambert law (or Beer's law) is the linear relationship between absorbance and concentration of an absorbing species. The general Beer-Lambert law is usually written as:
A = a(lambda) * b * c
where A is the measured absorbance, a(lambda) is a wavelength-dependent absorptivity coefficient, b is the path length, and c is the analyte concentration. When working in concentration units of molarity, the Beer-Lambert law is written as:
A = epsilon * b * c
where epsilon is the wavelength-dependent molar absorptivity coefficient with units of M -1 cm -1 .

## Who or what killed aunt Elda?

Anesthesia is a great tool for surgery, but it comes with price. Anesthesia, if given to high of a concentration, which is about forty percent concentration and higher, can lead to memory loss and even death. Is this what killed aunt Elda? Here is what we discovered.
The picture above is of the colorimeter and a sample of anesthesia.

## The Procedure

First we took and set up the colorimeter with the program that we used to record the data. The program that we chose to use was "logger pro". After setting up the colorimeter we took and measured samples of each concentration of anesthesia. Once we had collected our data we went into logger pro and added a line of best fit. From there we took the sample of anesthesia that was taken from aunt Elda's surgery, and put it into the colorimeter. The colorimeter found the absorbance of the sample for us. With the absorbancy of the sample and the line of best fit we were able to confirm that the percent concentration of the sample was about twenty five percent. Which is below the lethal dose of forty percent. This allowed us to conclude that the anesthesia that was used for aunt Elda did not kill her, we do not know what killed aunt Elda. (The above picture is of the type of colorimeter that we used.)

## What we found.

We know that if you have a concentration of over 40% of anesthesia, it can kill the patient. We wanted to know how aunt Elda died. We took samples from the anesthesia that was used on aunt Elda and compared them to samples from other concentrations of anesthesia. We found that if the percent concentration was above 40% about one-half of the anesthesia was absorbed, which as we know is not good. We put each sample through our colorimeter to see what the percent absorbance was. We were able to compare all of the samples because we knew what their percent concentration they were and found their absorbancy. Knowing this we found that the mystery sample that was taken from aunt Elda was put into the colorimeter and we found that it had an absorbance of 0.926 which compared to the other samples meant that the concentration of the sample must have been about a 25% concentration. Knowing this we are able to safely say that it was not the anesthesia that had killed aunt Elda.

## Meet The Author

Hi I'm Tanner I am the one that made this page. Have a good day! Thanks for checking out my page! Feel free to leave comments or suggestions or both!

## The following video is a brief description of how anesthesia works

How anesthesia works