posted by Catherine on .
Calculate the concentration of bromocresol green (BG) indicator
It says that Molar absorptivity = Absorbance at a wavelength/ concentration of BG indicator
I am having trouble calculating the concentration of BG.
Other info: Stock solution of BG = 80.0 mg/L and molar mass = 698.0 g/mol
We added 10.00 ml of stock solution to a 50.0 ml volumetric flask and diluted it to the line with 0.4M HCl
You don't have enough information posted to calculate concn.
First you need to calculate molar absorptivity, which as your post says is e = A/c (that comes from A = e*c)
If you used the diluted stock solution for that, you can calculate e by substituting the absorbance of the diluted stock solution.
Then you must have some other solution for which you want to calculate c, which can be done by A = e*c.
Post your additional information here if that is needed.