00:02
Okay, so we're told that at 251 nanometers, we have a concentration of a vitamin at 4 .79 times 10 to the minus 7 moles per liter.
00:17
And we're told that the absorbance at that particular wavelength is 0 .175.
00:24
And we're told that the path length, which either can be shown as an l or as a b, is one centimeter.
00:36
And we want to know what the molar absorptivity is.
00:41
And molar absorptivity is normally given either as an epsilon or an a.
00:47
We don't know.
00:49
Now, how are we going to be able to figure out what the molar absorptivity is? we're going to use beers law.
00:56
And beers law can be written one of two ways.
00:59
A is equal to epsilon times l times c.
01:05
Sometimes you'll see a written as a is equal to a, b, c.
01:10
So that's why i've written our values here for the path length and for the molar absorptivity two ways...