Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 22: Problem 4

The following organic compounds cannot exist. Why? a. 2 -chloro-2-butyne b. 2 -methyl-2-propanone c. \(1,\) l-dimethylbenzene d. 2 -pentanal e. 3 -hexanoic acid f. \(5,5\) -dibromo- \(-\) cyclobutanol

Short Answer

Expert verified
The given organic compounds cannot exist for the following reasons: a. 2-chloro-2-butyne: No place for chlorine to attach to the second carbon atom due to the triple bond. b. 2-methyl-2-propanone: Attaching a methyl group to the second carbon violates the octet rule. c. 1,1-dimethylbenzene: Attaching two methyl groups to one carbon in the benzene ring breaks the octet rule. d. 2-pentanal: No hydrogen atom connected to the second carbon for the aldehyde group. e. 3-hexanoic acid: Carboxylic acid functional group only bonds at the terminal carbon atom, not an internal one. f. 5,5-dibromo-cyclobutanol: No 5th carbon in a cyclobutanol molecule for bromine atoms to attach.

Step by step solution

01

a. 2-chloro-2-butyne

2-chloro-2-butyne implies that a chlorine atom is connected to the second carbon atom of a butyne molecule. Butyne has a triple bond between two of the carbon atoms. In the case of 2-butyne, the triple bond should be between the second and third carbon atoms. However, there is no place for the chlorine atom to attach to the second carbon atom, as it already has four bonds (one with the neighboring carbon, and three as part of the triple bond with the third carbon). This results in an invalid structure, so 2-chloro-2-butyne cannot exist.
02

b. 2-methyl-2-propanone

2-methyl-2-propanone implies that there is a methyl group attached to the second carbon atom of a propanone molecule. However, propanone (known as acetone) has only three carbon atoms with a carbonyl group (C=O) at the second carbon, and it is already bonded with the other two carbons. Adding a methyl group would violate the octet rule as the second carbon atom would have five bonds instead of the maximum of four. Thus, this compound cannot exist.
03

c. 1,1-dimethylbenzene

The name 1,1-dimethylbenzene implies that there are two methyl groups attached to the same carbon atom in the benzene ring. However, each carbon in a benzene ring is already attached to two neighboring carbon atoms, and one hydrogen atom, which means that there is only one available bond for the addition of a methyl group. Attaching two methyl groups on a single carbon breaks the octet rule. Therefore, the compound cannot exist. The correct compound is 1,2-dimethylbenzene, where two methyl groups are attached to adjacent carbon atoms.
04

d. 2-pentanal

2-pentanal implies there is an aldehyde functional group (C=O) attached at the second carbon atom of a pentane chain. However, in an aldehyde, the carbonyl carbon is bonded to a hydrogen and an alkyl group. In the case of 2-pentanal, there is no hydrogen atom connected to the second carbon atom, as it is bonded to two other carbon atoms from the alkyl chain. A correct compound with an aldehyde group would be pentanal instead of 2-pentanal, where the aldehyde group is connected at the end of the chain.
05

e. 3-hexanoic acid

3-hexanoic acid implies that a carboxylic acid functional group (COOH) is attached at the third carbon atom of the hexane chain. However, COOH functional groups only bond at the terminal carbon atom of an alkyl chain, not an internal one. There cannot be a hexanoic acid attached to the third carbon. A correct compound would be hexanoic acid, where the carboxylic acid group is connected to the end carbon atom.
06

f. 5,5-dibromo-cyclobutanol

5,5-dibromo-cyclobutanol implies that two bromine atoms are attached to the 5th carbon atom in the cyclobutanol molecule. However, cyclobutanol is a four-membered ring with an alcohol group (OH) attached to one of the carbon atoms. There is no 5th carbon in a cyclobutanol molecule, which means that 5,5-dibromo-cyclobutanol cannot exist. A correct compound might be 1,1-dibromo-cyclobutanol, in which two bromine atoms are attached to the first carbon atom.

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.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

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

Estimate \(\Delta H\) for the following reactions using bond energies given in Table \(8.5 .\) $$ 3 \mathrm{CH}_{2}=\mathrm{CH}_{2}(g)+3 \mathrm{H}_{2}(g) \rightarrow 3 \mathrm{CH}_{3}-\mathrm{CH}_{3}(g) $$ The enthalpies of formation for \(\mathrm{C}_{6} \mathrm{H}_{6}(g)\) and \(\mathrm{C}_{6} \mathrm{H}_{12}(g)\) are 82.9 and $-90.3 \mathrm{kJ} / \mathrm{mol}\( , respectively. Calculate \)\Delta H^{\circ}$ for the two reactions using standard enthalpies of formation from Appendix \( 4 .\) Account for any differences between the results obtained from the two methods.

Give two examples of saturated hydrocarbons. How many other atoms are bonded to each carbon in a saturated hydrocarbon?

Name all of the alcohols that have the formula $\mathrm{C}_{4} \mathrm{H}_{10} \mathrm{O}\( . How many ethers have the formula \)\mathrm{C}_{4} \mathrm{H}_{10} \mathrm{O} ?$

Three different organic compounds have the formula $\mathrm{C}_{3} \mathrm{H}_{8} \mathrm{O}$ . Only two of these isomers react with \(\mathrm{KMn} \mathrm{O}_{4}\) (a strong oxidizing agent). What are the names of the products when these isomers react with excess \(\mathrm{KMnO}_{4} ?\)

When acrylic polymers are burned, toxic fumes are produced. For example, in many airplane fires, more passenger deaths have been caused by breathing toxic fumes than by the fire itself. Using polyacrylonitrile as an example, what would you expect to be one of the most toxic, gaseous combustion products created in the reaction?
See all solutions

Recommended explanations on Chemistry Textbooks

Nuclear Chemistry

Read Explanation

Ionic and Molecular Compounds

Read Explanation

Chemistry Branches

Read Explanation

Organic Chemistry

Read Explanation

The Earths Atmosphere

Read Explanation

Making Measurements

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.

Sign-up for free