00:01
For this equation, you are given the linear equation for the standard curve as y equals 0 .0452x plus 0 .0074.
00:14
You're given the absorbances for each of your unknowns and you're asked to calculate the concentration.
00:19
So you simply plug those in and absorbance is y.
00:23
So 0 .189 equals 0 .0452x plus 0 .0074.
00:30
So we'll take 0 .189 minus 0 .0074 and that gives us 0 .1816 equals 0 .0452x.
00:42
Divide both sides by 0 .0452.
00:48
So divide by 0 .0452.
00:51
That tells us x, which is your concentration, is equal to 4 .02 micrograms per milliliter.
01:07
And then to figure out how many micrograms that would be, you would simply have to multiply it by the number of milliliters that you used for each sample.
01:19
So this is our concentration in micrograms per milliliter.
01:23
Nowhere in this question was i given the volume of the samples that you were testing.
01:31
Okay, so for unknown 2, it has an absorbance of 0 .111...