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1. Use the absorbance values you measured and the starch concentrations you calc

ID: 280296 • Letter: 1

Question

1. Use the absorbance values you measured and the starch concentrations you calculated to create a standard curve in a software program of your choice.Start by plotting a scatterplot of the data. Be sure to include all of the essential elements of a graph: a title, axis labels with units of measurement, and axis increments appropriate to the scale of your data. Finally include a line of best fit.

a. Copy and paste your graph into the space below.

b. What is your predicted concentration if you sampled a fourth cuvette and found the absorbance to be 0.35?

c. What is your predicted concentration if you sampled a fifth cuvette and found the absorbance to be 1.75?

Absorbance Starch Concentrations Cuvette 1 1.03 .002 mg/ml Cuvette 2 0.51 0.001 mg/ml Cuvette 3 0.26 0.0005 mg/ml

Explanation / Answer

a.

b. If absorbance = 0.35, what is the concentration?

y= 0.35

From the equation, y = 33.742x+0.3582

0.35 = 33.742x+0.3582

33.74x = 0.008

x= 0.008/33.74 = 0.00024

The concentration of 0.00024 mg/ml gives an absorbance of 0.35

c. If absorbance = 1.75

1.75 = 33.742x+0.3582

33.742x = 1.3918

x = 1.3918/33.742 = 0.0412 mg/mL

Conc (mg/ml) Abs 0.02 1.03 0.001 0.51 0.0005 0.26