Are the following pairs identical, enantiomers, diastereomers, or constitutional isomers?
c.
d.

a. Are d-erythrose and l-erythrose enantiomers or diastereomers?

b. Are l-erythrose and l-threose enantiomers or diastereomers?

For each pair, give the relationship between the two compounds. Making models will be helpful.

(e)

(f)

For each structure,

1. draw all the stereoisomers.

2. label each structure as chiral or achiral.

3. give the relationships between the stereoisomers (enantiomers, diastereomers).

(a)

Give the stereochemical relationships between each pair of structures. Examples are same compound, structural isomers, enantiomers, and diastereomers. Which pairs could you (theoretically) separate by distillation or recrystallization?

(a)

(b)

For each pair, give the relationship between the two compounds. Making models will be helpful.

(g)

Which of the following is a correct Fischer projection for $D_{-}\mathrm{glucose}$?

Given the wedge-and-dash structure of $2_{}$-bromobutanol with the following configuration: the hydroxyl group ($\mathrm{OH}$) is on a wedge at carbon 2, the bromine ($\mathrm{Br}$) is on a dash at carbon 2, and the methyl group ($\mathrm{CH}{3}_{}$) and hydrogen are in the plane, which Fischer projection correctly represents this molecule?

Which Fischer projection represents $D$-glucose?