Question

Assume for the purposes of this problem that to be an alcohol (-ol) or an amine (-amine), the hydroxyl or amino group must be bonded to a tetrahedral ( \(\left(p^{3}\right.\) hybridized) carbon atom. Write the structural formula of a compound with an unbranched chain of four carbon atoms that is an: (a) Alkane (b) Alkene (c) Alkyne (d) Alkanol (e) Alkenol (f) Alkynol (g) Alkanamine (h) Alkenamine (i) Alkynamine (j) Alkanal (k) Alkenal (1) Alkynal (m) Alkanone (n) Alkenone (o) Alkynone (p) Alkanoic acid (q) Alkenoic acid (r) Alkynoic acid

Short answer

#tag_title#(d) Alkanol #tag_content#Alkanols are compounds containing a hydroxyl (-OH) functional group attached to an alkane. The general formula for alkanols is \(C_{n}H_{2n+1}OH\). With four carbon atoms, the structural formula of an alkanol can be: ``` H H H H | | | | H - C-C-C-C - OH | | | | H H H H ``` #tag_title#(e) Alkenol #tag_content#Alkenols are compounds containing a hydroxyl (-OH) functional group attached to an alkene. With four carbon atoms, the structural formula of an alkenol can be: ``` H H H | | | H - C-C=C-C - OH | | H H ``` #tag_title#(f) Alkynol #tag_content#Alkynols are compounds containing a hydroxyl (-OH) functional group attached to an alkyne. With four carbon atoms, the structural formula of an alkynol can be: ``` H H | | H - C-C≡C-C - OH | H ```

Step-by-step solution

(a) Alkane

Alkanes are hydrocarbons with only single carbon-carbon bonds and are saturated. The general formula for alkanes would be \(C_{n}H_{2n+2}\). Thus, with four carbon atoms, the structural formula of an alkane would be: ``` H H H H | | | | H - C-C-C-C - H | | | | H H H H ```

(b) Alkene

Alkenes are hydrocarbons with at least one carbon-carbon double bond and are unsaturated. The general formula for alkenes would be \(C_{n}H_{2n}\). With four carbon atoms, the structural formula of an alkene can be: ``` H H H | | | H - C-C=C-C - H | | H H ```

(c) Alkyne

Alkynes are hydrocarbons with at least one carbon-carbon triple bond and are unsaturated. The general formula for alkynes is \(C_{n}H_{2n-2}\). With four carbon atoms, the structural formula of an alkyne can be: ``` H H | | H - C-C≡C-C - H | H ```

Key concepts

Alkane Structure

Alkanes are organic molecules composed entirely of carbon and hydrogen atoms, connected by single bonds. This forms a saturated molecular structure because there are no additional places for more hydrogen atoms to be attached.

For example, in an alkane with four carbon atoms, each carbon atom forms four bonds. These bonds connect to either other carbon atoms or hydrogen atoms. The structural formula for this straight-chain alkane, known as butane, can be visualized as follows:

H H H H | | | |H - C-C-C-C - H | | | | H H H H
This series of single bonds creates a stable structure with a general formula of \(C_{n}H_{2n+2}\) for alkanes, where 'n' represents the number of carbon atoms.

Alkene Structure

Alkenes differ from alkanes in that they contain at least one carbon-carbon double bond. This characteristic imparts different physical and chemical properties to the molecule. With the presence of a double bond, alkenes are considered unsaturated hydrocarbons.

The simplest alkene with four carbon atoms is butene, and its structure introduces the concept of isomerism because the double bond can be positioned at different locations along the chain. A typical representation of butene is:

H H H | | |H - C-C=C-C - H | | H H
The general formula for alkenes is \(C_{n}H_{2n}\), indicating half the number of hydrogen atoms compared to alkanes per carbon atom due to the presence of the double bond.

Alkyne Structure

Alkynes are more unsaturated than alkenes because they contain at least one carbon-carbon triple bond. This distinctive feature further reduces the number of hydrogen atoms that can be attached to the carbon chain compared to alkenes and alkanes.

An example of a four-carbon alkyne is butyne, and just like alkenes, the triple bond's position can lead to different isomers. The molecular structure of butyne can be depicted as:

H H | |H - C-C≡C-C - H | H
The general formula for these hydrocarbons is \(C_{n}H_{2n-2}\), reflecting even fewer hydrogen atoms in relation to the carbon atoms than in alkenes, due to the triple bond.

Alcohol Functional Group

Alcohols are organic compounds that contain one or more hydroxyl (-OH) groups attached to a carbon atom. The carbon to which the hydroxyl group is attached must be sp³ hybridized, indicating it is tetrahedral and connected to four other atoms.

An example of an alcohol with a four-carbon chain would be butanol. The alcohol group can be placed at different positions along the carbon backbone, leading to structural isomers with different physical and chemical properties. Here is a possible structure:

H H H H H-O| | | | |C--C--C--C-H H-O| | | | H H H HThe presence of the hydroxyl group significantly impacts the molecule's reactivity and solubility in water, distinguishing alcohols from hydrocarbons like alkanes, alkenes, and alkynes.

Amine Functional Group

Amines are another class of organic compounds and are characterized by one or more amino groups (-NH₂) attached to a carbon atom. Just like with alcohols, the carbon bonded to the amino group should be sp³ hybridized.

The simplest amine with an unbranched four-carbon chain is butanamine. The structure of an amine can also display isomerism, not just based on the carbon chain but also depending on where the amino group is attached. Butanamine's structure can be displayed as follows:

H H H H | H | | | | | NH - N--C--C--C--C - H | | | | | H H H H H

Amines are known for their basic properties and distinctive odor, and they are crucial in the synthesis of amino acids and pharmaceuticals.

Carbonyl Functional Group

The carbonyl functional group is a significant feature in various organic molecules, signified by a carbon atom double-bonded to an oxygen atom (C=O). This functional group is a characteristic of several subcategories of compounds, including aldehydes, ketones, carboxylic acids, and more.

A carbonyl group situated at the end of a carbon chain forms an aldehyde, whereas one placed within the carbon chain constitutes a ketone. As an example, a butanal (an aldehyde) structure on a four-carbon chain would look like this:

O || H - C - H |H - C - C - C - H | | | H H H
This particular functional group is extremely reactive and influences many chemical reactions that are important in both biological and industrial processes.

Carboxylic Acid Functional Group

Carboxylic acids represent a widespread group of organic compounds with a functional group that includes both a carbonyl and a hydroxyl group (COOH) attached to the same carbon atom. This arrangement renders carboxylic acids both polar and acidic.

In a four-carbon chain carboxylic acid, known as butanoic acid, the structure features the carboxylic acid group at the end of the chain. The molecular formula can be illustrated as follows:

O H || | H - C - OH |H - C - C - C - H | | | H H H
Carboxylic acids are found in various natural substances and are involved in numerous biochemical processes. Additionally, they are used in the production of polymers, pharmaceuticals, and solvents.