Chapter 23, Problem 80GP

Optical activity of biological molecules. Many biologically important molecules are optically active. When linearly polarized light traverses a solution of compounds containing these molecules, its plane of polarization is rotated. Some compounds rotate the polarization clockwise: others rotate the polarization counterclockwise. The amount of rotation depends on the amount of material in the path of the light. The following data give the amount of rotation through two amino acids over a path length of 100 cm:

Rotation (degrees)		Concentration (g/10C mL)
l-leucine	d-glutamic acid
−0.11	0.124	1.0
minus;0.22	0.248	2.0
−0.55	0.520	5.0
−1.10	1.24	10.0
−2.20	2.48	20.0
−5.50	6.20	50.0
−11.0	12.4	100.0

From these data find the relationship between the concentration C (in grams per 100 mL) and the rotation of the polarization (in degrees) of each amino acid. (Hint: Graph the concentration as a function of the rotation angle for each amino acid.)