Pure l-phenylalanine has a specific rotation of -35.1 degrees. What is the enantiomeric excess of a...

Pure l-phenylalanine has a specific rotation of -35.1 degrees. What is the enantiomeric excess of a 10.0 g/mL solution of phenylalanine which when placed in a standard 1.00 dm cell and analyzed in a polarimeter rotates plane polarized light -31.6 degrees?

Expert Solution

observed specific rotation = rotation / cell length x concentration

= -31.6 / 1 x 10

= -3.16 oC

enantiomeric excess = observed specific rotation x 100 / pure specific rotation

= -3.16 x 100 / -35.1

= 9.0 %

queen_honey_blossom answered 1 year ago

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