[blaisem]

Hello.

I recently ran a dilution on tetracyanobenzene to calculate its extinction coefficient.  I have run the experiment twice, and I am now working up the data.  I have 2.3% error between their values for epsilon.  I ran the second experiment at different concentrations because I knew by the second experiment about what concentration range would be ideal to observe the peaks I needed.  I determine epsilon from the slope of a linear regression through the origin.

I have two questions.

First:
To calculate the molar absorptivity, is it appropriate to simply average the epsilon values gained from both runs, or should I combine all of my data points from both experiments into one plot, run a linear regression, and calculate epsilon from there?

Second:
If I should average the epsilon values from each experiment, how do I report my R² value?  Do I average it as well?

I know these are questions of a statistical nature, but if anyone can help, I appreciate the advice!