/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 23 Propose structures and represent... [FREE SOLUTION] | 91影视

91影视

Log out

Learning Materials

Features

Discover

Chapter 23: Problem 23

Propose structures and represent structures with line drawings for molecules that fit the following descriptions: (a) \(\mathrm{C}_{3} \mathrm{H}_{6} \mathrm{O} ;\) contains an aldehyde functional group (b) \(\mathrm{C}_{3} \mathrm{H}_{6} \mathrm{O}_{2}\), contains a carboxylic acid functional group (c) \(\mathrm{C}_{4} \mathrm{H}_{8} \mathrm{O}_{2}\); two isomers that contain ester groups (d) \(\mathrm{C}_{6} \mathrm{H}_{13} \mathrm{~N}\), a cyclic structure with an amine group

Short Answer

Expert verified
(a) Propanal, (b) Propanoic acid, (c) Ethyl acetate and Methyl propanoate, (d) Piperidine.

Step by step solution

01

Understand the Molecular Formula and Functional Group for (a)

The molecular formula given is \( \mathrm{C}_{3} \mathrm{H}_{6} \mathrm{O} \), and the structure should include an aldehyde functional group, which is represented by \(-\mathrm{CHO}\). An aldehyde group is typically located at the end of a carbon chain, where the carbon atom is double-bonded to oxygen \(\mathrm{C}=\mathrm{O}\) and single-bonded to hydrogen \(\mathrm{C}-\mathrm{H}\).
02

Construct the Structure for (a)

To form a molecule that fits the formula \(\mathrm{C}_{3} \mathrm{H}_{6} \mathrm{O}\) with an aldehyde group, we can draw the structure of propanal: ```CH3-CH2-CHO```This shows a three-carbon chain with the aldehyde group on the terminal carbon.
03

Understand the Molecular Formula and Functional Group for (b)

The formula is \( \mathrm{C}_{3} \mathrm{H}_{6} \mathrm{O}_{2} \), indicating a carboxylic acid functional group, which includes \(-\mathrm{COOH}\). This group is also typically at the end of a carbon chain.
04

Construct the Structure for (b)

The molecule that fits \(\mathrm{C}_{3} \mathrm{H}_{6} \mathrm{O}_{2}\) as a carboxylic acid is propanoic acid: ```CH3-CH2-COOH```The structure shows three carbon atoms with a carboxylic acid group on the terminal carbon.
05

Understand the Molecular Formula and Isomer Requirement for (c)

The formula here is \( \mathrm{C}_{4} \mathrm{H}_{8} \mathrm{O}_{2} \), and we need to find two isomers that contain ester groups. An ester is typically written \(-\mathrm{COOR}\), where \(\mathrm{R}\) is a hydrocarbon group.
06

Construct Isomer 1 for (c)

One possible ester isomer is ethyl acetate, where the ester group is between the first and second carbon: ``` CH3-COO-CH2-CH3 ``` It shows a four-carbon chain with an ester functional group between the carbons.
07

Construct Isomer 2 for (c)

Another isomer is methyl propanoate, where the ester group is moved: ```CH3-CH2-COO-CH3```This structure also fits \(\mathrm{C}_{4} \mathrm{H}_{8} \mathrm{O}_{2}\) but positions the ester group differently.
08

Understand the Cyclic Requirement and Amine Group for (d)

The formula is \( \mathrm{C}_{6} \mathrm{H}_{13} \mathrm{~N} \), and it must form a ring structure containing an amine group \(-\mathrm{NH}-\). This suggests a typical secondary cyclic amine.
09

Construct the Cyclic Structure for (d)

A molecule that fits is an azacyclohexane or piperidine, a six-membered ring with an amine: ``` C1-C2 | | N-C6-C3 | | C5-C4 ``` This is a cyclic structure where one carbon is replaced by a nitrogen atom, maintaining the amine group functionality.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91影视!

Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Functional Groups
Functional groups are specific groups of atoms within molecules that are responsible for the characteristic chemical reactions of those molecules. They play a crucial role in organic chemistry, as they determine the properties and reactions of compounds.
For example, the aldehyde group (\(-CHO\)) in propanal gives it its distinct reactivity. Aldehydes typically occur at the end of a carbon chain and feature a carbon double-bonded to oxygen and single-bonded to hydrogen.
  • Aldehyde (-CHO): Found at the end of carbon chains.
  • Carboxylic acid (-COOH): A terminal group with acidic properties.
  • Ester (-COOR): Formed by reactions between acids and alcohols.
  • Amine (-NH-): Found in amines, contributes to basicity.
Understanding functional groups helps predict how molecules will interact with others.
Molecular Formulas
Molecular formulas provide the number and type of atoms in a molecule. They are essential for identifying the molecule and understanding its composition. For example, \(\mathrm{C}_{3} \mathrm{H}_{6} \mathrm{O}\) denotes three carbons, six hydrogens, and one oxygen.
This information helps chemists determine the possible structures a molecule might have, often in combination with functional groups like aldehydes or carboxylic acids.
  • Gives basic composition of molecules.
  • Helps identify possible structures.
  • Aids in understanding chemical behavior.
It serves as a foundation for constructing and visualizing different molecular structures.
Isomerism
Isomerism occurs when two or more compounds share the same molecular formula but differ in structure or arrangement. They can have vastly different properties despite having the same atoms.
For instance, \(\mathrm{C}_{4} \mathrm{H}_{8} \mathrm{O}_{2}\) can form various isomers with ester groups, like ethyl acetate and methyl propanoate. These differ in the position of the ester group.
  • Structural isomers: Different connectivity of atoms.
  • Stereoisomers: Same connectivity, different spatial arrangement.
  • Important for predicting physical and chemical properties.
Understanding isomerism is key to exploring the diversity and complexity of organic molecules.
Chemical Structure Drawing
Chemical structure drawing is a visual representation of a molecule's structure, showing how atoms are connected. It is crucial for understanding molecular geometry and bonding patterns.
For instance, drawing the structure of azacyclohexane includes depicting a six-membered ring with an amine group. This illustrates the cyclic nature and the specific arrangement of atoms.
  • Line drawings: Simplified representations focusing on connectivity.
  • Shows functional groups and bonds clearly.
  • Aids in grasping molecular shape and behavior.
These drawings are essential for chemists to communicate ideas and predict reactions.

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Write representative structures for the following: (a) \(\mathrm{A}\) fat (b) A vegetable oil (c) An aldotetrose

In the molecule below, the triple bond has one \(\pi\) bond that is in conjugation with the neighboring double bond, and it has one \(\pi\) bond that is not conjugated. Visualize a simplified orbital overlap picture and explain why one \(\pi\) bond of the triple bond has delocalized electrons, but the other does not. (The hybridization of each atom is indicated.)

The relative amount of unsaturation in a fat or oil is expressed as an iodine number. Olive oil, for instance, is highly unsaturated and has an iodine number of 172, while butter is much less unsaturated and has an iodine number of \(37 .\) Defined as the number of grams of \(\mathrm{I}_{2}\) absorbed per 100 grams of fat, the iodine number is based on the fact that the carbon-carbon double bonds in fats and oils undergo an addition reaction with \(\mathrm{I}_{2}\). The larger the number of double bonds, the larger the amount of \(\mathrm{I}_{2}\) that reacts. To determine an iodine number, a known amount of fat is treated with a known amount of \(\mathrm{I}_{2}\). When the addition reaction is complete, the amount of excess \(\mathrm{I}_{2}\) remaining is determined by titration with \(\mathrm{Na}_{2} \mathrm{~S}_{2} \mathrm{O}_{3}\) according to the equation $$ 2 \mathrm{Na}_{2} \mathrm{~S}_{2} \mathrm{O}_{3}(a q)+\mathrm{I}_{2}(a q) \rightarrow \mathrm{Na}_{2} \mathrm{~S}_{4} \mathrm{O}_{6}(a q)+2 \mathrm{NaI}(a q) $$ Knowing both the amount of \(\mathrm{I}_{2}\) originally added and the amount remaining after reaction, the iodine number can be calculated. Assume that \(0.500 \mathrm{~g}\) of human milk fat is allowed to react with \(25.0 \mathrm{~mL}\) of \(0.200 \mathrm{M} \mathrm{I}_{2}\) solution and that \(81.99 \mathrm{~mL}\) of \(0.100\) \(\mathrm{M} \mathrm{Na}_{2} \mathrm{~S}_{2} \mathrm{O}_{3}\) is required for complete reaction with the excess \(\mathrm{I}_{2}\). (a) What amount (in grams) of \(\mathrm{I}_{2}\) was added initially? (b) How many grams of \(\mathrm{I}_{2}\) reacted with the milk fat, and how many grams were in excess? (c) What is the iodine number of human milk fat? (d) Assuming a molecular weight of 800 , how many double bonds does an average molecule of milk fat contain?

Unlike palmerolide A (Problem \(23.80\) ), which has a large ring, a cyclic molecule with only six atoms can only have a cis double bond, but not a trans double bond. Give a line drawing of a cyclic molecule with six carbon atoms and a cis double bond. Explain why it cannot have a trans double bond.

Give line drawings for each of the following compounds: (a) 3-Ethylhexane (b) \(2,2,3\) -Trimethylpentane (c) 3-Ethyl-3,4-dimethylheptane (d) 5-Isopropyl-2-methyloctane
See all solutions

Recommended explanations on Chemistry Textbooks

Physical Chemistry

Read Explanation

Inorganic Chemistry

Read Explanation

Organic Chemistry

Read Explanation

Chemistry Branches

Read Explanation

Making Measurements

Read Explanation

Ionic and Molecular Compounds

Read Explanation
View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.