How many asymmetric centers are present in the compound $2_{\text{-}}\text{chlorobutane}$?

• A. $1$
• B. $3$
• C. $2$
• D. $0$

Answer: (A)

Verified step by step guidance

1. Identify the structure of 2-chlorobutane. It is a four-carbon chain (butane) with a chlorine atom attached to the second carbon.
2. Recall that an asymmetric center (chiral center) is a carbon atom bonded to four different groups.
3. Examine each carbon in 2-chlorobutane to see if it is bonded to four different substituents:
4. - Carbon 1 is bonded to three hydrogens and carbon 2, so it is not asymmetric.
5. - Carbon 2 is bonded to chlorine, carbon 1, carbon 3, and a hydrogen, all different groups, so it is an asymmetric center.
6. - Carbon 3 is bonded to carbon 2, carbon 4, and two hydrogens, so it is not asymmetric.
7. - Carbon 4 is bonded to three hydrogens and carbon 3, so it is not asymmetric.
8. Conclude that there is only one asymmetric center in 2-chlorobutane, located at carbon 2.