Menthol can be isolated from the peppermint plant and is responsible for the characteristic flavor and taste of peppermint. (-)-Menthol is optically active, its specific rotation [?D] = -58 ? at 20 ?C. The structure of (-)-menthol is shown below.

The instructional lab purchase a bottle of menthol at a large discount. When the bottle arrived it was not labeled as (-)-menthol. A sample from this bottle gave a specific rotation of -12 ? at 20 ?C.

Calculate the percent enantiomeric excess of the contents of the bottle labeled as just menthol.

For the purchased sample what percentage of (-)-menthol is indicated by this measurement?

For an enantiomerically pure sample of (-)-Menthol, what would be the observed rotation over a 1.0 dm pathlength for a solution if 0.8 grams of (-)-Menthol were dissolved in ethanol (10mL total volume). The density of menthol is 0.89g/mL3 at 20 ?C.