Problem 85 - Chemistry The Central Science

Question

Chloropropane is derived from propane by substituting Cl for \(\mathrm{H}\) on one of the carbon atoms. (a) Draw the structural formulas for the two isomers of chloropropane. (b) Suggest names for these two compounds.

Step-by-Step Solution

Answer

The two isomers of chloropropane are 1-chloropropane and 2-chloropropane. Their structural formulas are: 1-chloropropane: \(H H H\)\ \(| | |\) \(C-C-C-Cl\) \(| | |\) \(H H H\) 2-chloropropane: \(H H \ \ H\)\ \(| | \ \ |\) \(C-C-Cl-C-H\) \(| | \ \ |\) \(H H \ \ H\) The suggested names for these compounds are "1-chloropropane" and "2-chloropropane" respectively.

Step 1: List the possible structures and their IUPAC names

To draw the structural formulas for chloropropane, we will start with the propane structure which has three carbon atoms. By replacing one of the hydrogens with chlorine, we can obtain different isomers of chloropropane. There are three possible structural isomers for chloropropane: 1. Chlorine is attached to the first carbon atom: 1-chloropropane (Molecular formula: \(CH_3CH_2CH_2Cl\)) 2. Chlorine is attached to the second carbon atom: 2-chloropropane (Molecular formula: \(CH_3CHClCH_3\)) These two structures have different molecular formulas, so they are classified as different isomers.

Step 2: Draw the structural formulas for the two isomers

Now we will draw the structural formulas for the two isomers mentioned in step 1: 1. 1-chloropropane: In 1-chloropropane, the chlorine atom replaces one hydrogen atom in the first carbon, which forms a structure as follows: \(H H H\)\ \(| | |\) \(C-C-C-Cl\) \(| | |\) \(H H H\) 2. 2-chloropropane: In 2-chloropropane, the chlorine atom replaces one hydrogen atom in the second carbon, which forms a structure as follows: \(H H \ \ H\)\ \(| | \ \ |\) \(C-C-Cl-C-H\) \(| | \ \ |\) \(H H \ \ H\)

Step 3: Suggest names for the two compounds

Based on the structural formulas and their IUPAC names, we can suggest the following names for these two compounds: a) The first compound (1-chloropropane) can be simply called "1-chloropropane" b) The second compound (2-chloropropane) can be simply called "2-chloropropane" In conclusion, the two isomers of chloropropane are 1-chloropropane and 2-chloropropane. Their structural formulas are drawn above, and their suggested names are "1-chloropropane" and "2-chloropropane" respectively.