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Determine the number of stereoisomers of 2-chlorobutane considering chirality and explain how the configuration of the stereoisomers differ.

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2-chlorobutane has one chiral center, which is the carbon atom bonded to the chlorine atom  C2 . A chiral center is an atom that has four different groups attached to it, and in this case, the C2 atom is bonded to a hydrogen, a chlorine, a methyl group  CH3 , and an ethyl group  C2H5 .Since there is only one chiral center, we can use the formula 2^n to determine the number of stereoisomers, where n is the number of chiral centers. In this case, n = 1, so there are 2^1 = 2 stereoisomers for 2-chlorobutane.The two stereoisomers are enantiomers, which are non-superimposable mirror images of each other. They have the same molecular formula and connectivity, but they differ in the spatial arrangement of the atoms around the chiral center. The configuration of the stereoisomers can be described using the Cahn-Ingold-Prelog  CIP  priority rules and the R/S system.1. Assign priorities to the four groups attached to the chiral center based on their atomic number. The group with the highest atomic number gets the highest priority  1 , and the group with the lowest atomic number gets the lowest priority  4 . In this case, the priorities are: Cl  1 , C2H5  2 , CH3  3 , and H  4 .2. Orient the molecule so that the lowest priority group  H  is pointing away from you. If the remaining groups are arranged in a clockwise order from highest to lowest priority  1-2-3 , the configuration is R  rectus . If the order is counterclockwise  1-3-2 , the configuration is S  sinister .For 2-chlorobutane, the two stereoisomers are:1.  R -2-chlorobutane: The groups around the chiral center are arranged in a clockwise order  Cl-C2H5-CH3  when the hydrogen is pointing away.2.  S -2-chlorobutane: The groups around the chiral center are arranged in a counterclockwise order  Cl-CH3-C2H5  when the hydrogen is pointing away.These two enantiomers have different configurations around the chiral center, and they will exhibit different optical properties, such as rotating plane-polarized light in opposite directions.
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