First molar

Well done -- I promise that the next time you face this sort of graphical calculation, it will make more sense. And as you've found, it's all about the units.

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Yes, that sounds too low, at least for those wavelengths where methyl red absorbs strongly. Did you correct your concentrations for the dilution you made as you mixed your stock solution into liquid prior to making the spectrometer measurement?

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... slope makes sense given the graph you see. By the way, using the above i got 0.01871m-1 cm-1 for methyl red....is this value not too small for the molar extinction coefficient though?

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Hey, :) need help working this out: pH: 4 molar extinction coefficient: 0.0187142857 m-1cm-1 absorbance at 500nm: 1.492 [Acid form]?? (work out using molar extinction coefficient) [base form]? lg([acid]/[base])? pKa? If someone can guide me on ...

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Once you have plotted the data and drawn the line, the slope is the rise/run, the dy/dx. You can count squares on the graph paper. On the other hand, you can put the values of x and y into a spreadsheet and run a linear regression. If you do that, be sure to go back to the raw data on a graph and ma...

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