Concept explainers
Interpretation : The specific rotation of a substance dissolved in a solvent (0.4 g/mL) and with observed rotation of -10° is to be determined.
Concept Introduction : The specific rotation (
Answer to Problem 1P
Specific rotation = -50° mL/g.dm
Explanation of Solution
Given information :
Observed rotation,
Length of the sample tube, l = 0.5 dm
Concentration of solvent, C = 0.4 g/mL
:
The formula to calculate the specific rotation (
In this formula,
C is the concentration in g/mL
l is the length of the sample tube in unit dm.
T is the temperature which is taken as a constant at 25°C.
? is the
Now, put the given data in this formula and solve for the specific rotation of the given substance.
The specific rotation of the given substance is -50° mL/g.dm.
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Chapter 92 Solutions
EBK A SMALL SCALE APPROACH TO ORGANIC L
- Calculate the specific rotation of a solution of a compound (30.0 g/100 mL of solution) that has a measured rotation of +25.25º in a 2.00 dm tube.arrow_forwardAn unknown sugar is known to equilibrate between two forms, I and II, in aqueous solution. Thisequilibration can be followed by measuring the optical rotation of aqueous solutions of isolatedsamples of form I and II. When species I was dissolved in pure water and the optical rotation was measured, it gave aspecific rotation of [?] = +42.0°. Over time, this value decreased to a constant value of [?]= +0.2°. • When species II was dissolved in pure water and the optical rotation was measured, it gave aspecific rotation of [?] = -54.0°. Over time, this value decreased to constant value of [?]= +0.2°. • In each case, both forms I and II were shown to be present in the mixture at the end of theexperiment. Calculate the ratio of the two forms I and II present at equilibrium and comment on anyassumptions made in making that calculation.arrow_forwardCalculate the specific rotation of a substance that is dissolved in a solvent (0.4 g/mL) and that has an observed rotation of –10° as determined with a 0.5-dm cell.arrow_forward
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- EBK A SMALL SCALE APPROACH TO ORGANIC LChemistryISBN:9781305446021Author:LampmanPublisher:CENGAGE LEARNING - CONSIGNMENTOrganic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning