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Determine the specific rotation of epinephrine


Problem:

 A solution of 0.50 g of (-)-epinephrine dissolved in 10.0 mL of dilute aqueous HCl was placed in a 
20-cm polarimeter tube. Using the sodium D line, the rotation was found to be -5.1° at 25 °C. Determine the specific rotation of epinephrine.

 Solution:

 Specific rotation can be determined with a formula:
Where a is an observed rotation (degrees), 
c is a concentration (g/mL) and 
l is the length of the tube (dm).

T = 25°C
λ=D, that means a sodium line (589 nm)

Answer: specific rotation of epinephrine is – 51.

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