Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

1. Compare Beer\'s law with the equation of a line. Identify x (the independent

ID: 1047561 • Letter: 1

Question

1. Compare Beer's law with the equation of a line. Identify x (the independent variable), y (the dependent variable), m, and b using the terms in Beer's law
2. What is a calibration curve? And how is it used in an experiment? 1. Compare Beer's law with the equation of a line. Identify x (the independent variable), y (the dependent variable), m, and b using the terms in Beer's law
2. What is a calibration curve? And how is it used in an experiment?
2. What is a calibration curve? And how is it used in an experiment?

Explanation / Answer

1.

Beer's law equation : A = cl

straight line equation: y = mx + b

x = the independent variable = c (concentration)

y = the dependent variable = A (absorbance)

m = slope =   x l =   (for unit cell length, l = 1)

b = intercept = 0

2.

A calibration curve is a method for determining the unknown concentration of a substance in an sample by comparing standard samples of known concentration to the unknown

At first a set of experiments are performed to obtain the absorbance (A) value of set of known concentrations (c). Then A is plotted against c to get a standard calibration curve which is a straight line passing through origin for Beer's law experiment. Then when a unknown concentration is need to know of that particular sample, just measure the absorbance (A) value of the unknown sample and evaluate the concentration from the calibration curve.