Write hond-line structural formalas for (a) two primary alcohols

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Write hond-line structural formalas for (a) two primary alcohols, (b) a secondary alcohol, and (c) a tertiary alcohol-all having the molecular formula CHO One way of naming alcohols is to name the alkyl group that is attached to the OH and add the word alabel Write bond-line formulas for (a) propyl alcohol and (b) isopropyl alcohol.

The Correct Answer and Explanation is :

Let’s break this down:

(a) Two primary alcohols

A primary alcohol has the general structure where the -OH group is attached to a carbon atom that is only bonded to one other carbon (i.e., it’s a terminal carbon). For alcohols with the molecular formula C₃H₆O (CHO), the possible primary alcohols are:

  1. 1-Propanol:
  • Bond-line formula:
   CH₃-CH₂-CH₂OH

Here, the -OH group is attached to the terminal carbon (the last carbon), making it a primary alcohol.

  1. 2-Propanol (though secondary, for completeness):
  • Bond-line formula:
   CH₃-CH(OH)-CH₃

(b) A secondary alcohol

A secondary alcohol has the -OH group attached to a carbon that is bonded to two other carbons. For a molecular formula of C₃H₆O, the only secondary alcohol is:

  • 2-Propanol (Isopropanol):
  • Bond-line formula:
  CH₃-CH(OH)-CH₃

The hydroxyl group is attached to the second carbon, which is bonded to two other carbons, making it a secondary alcohol.

(c) A tertiary alcohol

A tertiary alcohol has the -OH group attached to a carbon that is bonded to three other carbons. However, with the molecular formula CHO, a tertiary alcohol is not possible because there aren’t enough carbons to attach to three other groups while also accommodating the -OH group.

(a) Propyl alcohol and (b) Isopropyl alcohol

Now let’s look at the bond-line formulas:

  • Propyl Alcohol (1-Propanol):
  • Bond-line formula:
  CH₃-CH₂-CH₂OH
  • Isopropyl Alcohol (2-Propanol):
  • Bond-line formula:
  CH₃-CH(OH)-CH₃

Explanation:

  • Primary alcohols: These have the hydroxyl (-OH) group attached to a carbon that is connected to only one other carbon. In 1-propanol, the terminal carbon carries the -OH group, thus making it a primary alcohol.
  • Secondary alcohols: The -OH group is attached to a carbon connected to two other carbons. In 2-propanol (isopropyl alcohol), the central carbon carries the -OH group and is attached to two other carbon atoms.
  • Tertiary alcohols: The -OH group would be attached to a carbon that is connected to three other carbons. However, with a molecular formula of C₃H₆O, it isn’t possible to form a tertiary alcohol because of the limited number of carbon atoms.

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