If you have an equation for a line, y = 0.15x + 0.010, where y is absorbance and x is concentration in molarity of Fe (2+), calculate the concentration of a test sample with an absorbance of 0.065.
What is the absorbance value for the blank in this experiment?
.065 = .15 x + .01
.15 x = .055
x = 5.5/15
To find the absorbance value for the blank in this experiment, we need to substitute the concentration of the blank into the equation and solve for absorbance (y).
The equation for the line is y = 0.15x + 0.010, where y represents absorbance and x represents concentration. We are given the absorbance value for the test sample, which is 0.065.
To find the concentration of the test sample, we need to rearrange the equation as follows:
0.065 = 0.15x + 0.010
To isolate x (concentration), we subtract 0.010 from both sides:
0.065 - 0.010 = 0.15x
Simplifying the equation yields:
0.055 = 0.15x
Now, to find the value of x, we divide both sides by 0.15:
0.055 / 0.15 = x
This gives us the concentration of the test sample, x = 0.3667 M.
However, the question asks for the absorbance value for the blank in this experiment. The blank refers to a sample with zero concentration. Hence, to find the absorbance value for the blank, we substitute x = 0 into the equation:
y = 0.15(0) + 0.010
y = 0 + 0.010
y = 0.010
Therefore, the absorbance value for the blank in this experiment is 0.010.