Steroisomers: Enantiomers, Diastereomers, or Not

Pairs of possible stereoisomers of 2,4-dichloropentane are show in each row below.  R/S designations of each chiral carbon are also shown.  Rotate one member of each row pair to see if the molecules are superimposable (identical), if they are nonsuperimposable AND are mirror images (enantiomers), or if they are nonsuperimposable AND are NOT mirror images (diastereomers).  Then look at the R/S designations to see a pattern that should support your answer. 

For answers, build the molecules yourself using the following link:  Stereochemical Challenge

Molecule

Jmol Model

 

Jmol Model

(2R,4R)- and
(2S,4S)- 2-bromo-4-chloropentane.
1.  Are these identical mirror images of each other?
2.  Are they enantiomers?
3.  Are they diastereomers?
4.  Are they identical?

 

 

(2R,4S)- and
(2S,4R)- 2-bromo-4-chloropentane.
1.  Are these identical mirror images of each other?
2.  Are they enantiomers?
3.  Are they diastereomers?
4.  Are they identical?
 

 

 

(2R,4R)- and
(2R,4S)- 2-bromo-4-chloropentane.
1.  Are these identical mirror images of each other?
2.  Are they enantiomers?
3.  Are they diastereomers?
4.  Are they identical?