Beer's Law Chemistry Lab

If my slope is .1343, the y-int is -.0427, and the r2 value is .9772, the absorbance is .376 how would i get the phosphate concentration?
I have already gotten this problem wrong and the answer is supposed to be 3.12 but i dont know how to arrive at this answer. If you could show me it would help me a lot!

since beer's law is

A = ε x L x c + 0

which looks a lot like
y = m x + b
providing y = A, m = εL, slope = 0

therefore...
a plot of A on the y-axis and c on the x-axis will give slope = ε x L and intercept = 0

and in your case.. looks like you didn't set the intercept to 0 when you did your excel plot.. but.. I'll use your data anyway.....

If I start with
A = slope x c + intercept...

I generate this equation...
A = 0.1343 x c - 0.0427

rearranging..
c = (A + 0.0427) / 0.1343

solving for A = 0.376
c = (0.376 + 0.0427) / 0.1343 = 3.12

************
questions?

what's the actual data?

welcome

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A=ecl is similar to y=mx+b

you have your absorbance slope and y intercept.

concentration should be your absorbance reading divided by your slope.

it may not be exactly that 3.12 depending on your readings and lab environment