Question

Draw as many compounds as you can that fit the following descriptions: (a) Alcohols with formula \(\mathrm{C}_{4} \mathrm{H}_{10} \mathrm{O}\) (b) Amines with formula \(\mathrm{C}_{5} \mathrm{H}_{13} \mathrm{~N}\) (c) Ketones with formula \(\mathrm{C}_{5} \mathrm{H}_{10} \mathrm{O}\) (d) Aldehydes with formula \(\mathrm{C}_{5} \mathrm{H}_{10} \mathrm{O}\) (e) Esters with formula \(\mathrm{C}_{4} \mathrm{H}_{8} \mathrm{O}_{2}\) (f) Ethers with formula \(\mathrm{C}_{4} \mathrm{H}_{10} \mathrm{O}\)

Short answer

Multiple structures can fit each category, resulting in 4 alcohols, 5 amines, 3 ketones, 3 aldehydes, 4 esters, and 3 ethers.

Step-by-step solution

Alcohols with Formula C₄H₁₀O

An alcohol is characterized by an hydroxyl group (-OH) attached to a carbon atom. For C₄H₁₀O, possible structures are: 1. **n-Butanol:** CH₃-(CH₂)₃-OH 2. **sec-Butanol:** CH₃-CH(OH)-CH₂-CH₃ 3. **isobutanol:** (CH₃)₂CH-CH₂-OH 4. **tert-Butanol:** (CH₃)₃C-OH

Amines with Formula C₅H₁₃N

Amines contain a nitrogen atom bonded to alkyl groups. For the formula C₅H₁₃N, structures include: 1. **n-Pentylamine:** CH₃-(CH₂)₄-NH₂ 2. **Isopentylamine:** (CH₃)₂CH-CH₂-CH₂-NH₂ 3. **Neopentylamine:** (CH₃)₃C-CH₂-NH₂ 4. **2-Methylbutan-1-amine:** CH₃-CH(CH₃)-CH₂-CH₂-NH₂ 5. **3-Methylbutan-1-amine:** CH₃-CH₂-CH(CH₃)-CH₂-NH₂

Ketones with Formula C₅H₁₀O

Ketones have a carbonyl group (C=O) within the carbon chain. For C₅H₁₀O, potential structures are: 1. **2-Pentanone:** CH₃-CH₂-CO-CH₂-CH₃ 2. **3-Pentanone:** CH₃-CO-(CH₂)₂-CH₃ 3. **3-Methylbutan-2-one:** (CH₃)₂CH-CO-CH₃

Aldehydes with Formula C₅H₁₀O

Aldehydes contain a carbonyl group (C=O) at the end of the carbon chain. For C₅H₁₀O, structures include: 1. **Pentanal:** CH₃-(CH₂)₃-CHO 2. **2-Methylbutanal:** (CH₃)₂CH-CH₂-CHO 3. **3-Methylbutanal:** CH₃-CH(CH₃)-CH₂-CHO

Esters with Formula C₄H₈O₂

Esters feature a central carbon double-bonded to oxygen and single-bonded to another oxygen atom, which is bonded to an alkyl group. C₄H₈O₂ structures include: 1. **Methyl propanoate:** CH₃-CH₂-COO-CH₃ 2. **Ethyl acetate:** CH₃-COO-CH₂-CH₃ 3. **Propyl formate:** HCOO-CH₂-CH₂-CH₃ 4. **Isopropyl formate:** HCOO-(CH₃)₂CH

Ethers with Formula C₄H₁₀O

Ethers have an oxygen atom connected to two alkyl or aryl groups. For C₄H₁₀O, possible structures are: 1. **Diethyl ether:** CH₃-CH₂-O-CH₂-CH₃ 2. **Methyl propyl ether:** CH₃-O-CH₂-CH₂-CH₃ 3. **Ethyl methyl ether:** CH₃-O-CH₂-CH₃

Key concepts

Alcohols

Alcohols are organic compounds distinguished by the presence of a hydroxyl group, (-OH), attached to a carbon atom. This hydroxyl group is responsible for the characteristic properties of alcohols, such as solubility in water and a distinct smell. In particular, for a compound with the formula \(\mathrm{C}_{4}\mathrm{H}_{10}\mathrm{O}\), several isomers can be drawn:

• n-Butanol: This is a straight-chain alcohol represented as \(\mathrm{CH}_{3}-(\mathrm{CH}_{2})_{3}-\mathrm{OH}\).
• sec-Butanol: The hydroxyl group is attached to the second carbon, giving the formula \(\mathrm{CH}_{3}-\mathrm{CH}(\mathrm{OH})-\mathrm{CH}_{2}-\mathrm{CH}_{3}\).
• Isobutanol: Here, the structure branches with the formula \((\mathrm{CH}_{3})_{2}\mathrm{CH}-\mathrm{CH}_{2}-\mathrm{OH}\).
• tert-Butanol: This is a more branched isomer with the formula \((\mathrm{CH}_{3})_{3}\mathrm{C}-\mathrm{OH}\).

These variations or isomers create unique properties despite having the same molecular formula.

Amines

Amines are compounds that feature a nitrogen atom bonded to hydrogen atoms, alkyl groups, or both. The nitrogen is key to the amine group's identity and significantly influences the compound's properties, such as basicity and reactivity. For the molecular formula \(\mathrm{C}_{5}\mathrm{H}_{13}\mathrm{N}\), one can deduce various structures:

• n-Pentylamine: The simplest straight chain, \(\mathrm{CH}_{3}-(\mathrm{CH}_{2})_{4}-\mathrm{NH}_{2}\).
• Isopentylamine: A branched version is \((\mathrm{CH}_{3})_{2}\mathrm{CH}-\mathrm{CH}_{2}-\mathrm{CH}_{2}-\mathrm{NH}_{2}\).
• Neopentylamine: Another branched isomer with structure \((\mathrm{CH}_{3})_{3}\mathrm{C}-\mathrm{CH}_{2}-\mathrm{NH}_{2}\).
• 2-Methylbutan-1-amine: Combining branching and a linear chain: \(\mathrm{CH}_{3}-\mathrm{CH}(\mathrm{CH}_{3})-\mathrm{CH}_{2}-\mathrm{CH}_{2}-\mathrm{NH}_{2}\).
• 3-Methylbutan-1-amine: This structure: \(\mathrm{CH}_{3}-\mathrm{CH}_{2}-\mathrm{CH}(\mathrm{CH}_{3})-\mathrm{CH}_{2}-\mathrm{NH}_{2}\).

Each of these isomers exhibits different chemical and physical properties while sharing a common formula.

Ketones

Ketones are organic compounds that contain a carbonyl group, \((\mathrm{C}=\mathrm{O})\), bonded to two other carbon atoms within a carbon chain. This internal carbonyl placement distinguishes ketones from aldehydes. For a ketone with the formula \(\mathrm{C}_{5}\mathrm{H}_{10}\mathrm{O}\):

• 2-Pentanone: This ketone has its carbonyl group on the second position: \(\mathrm{CH}_{3}-\mathrm{CH}_{2}-\mathrm{CO}-\mathrm{CH}_{2}-\mathrm{CH}_{3}\).
• 3-Pentanone: Another structure is \(\mathrm{CH}_{3}-\mathrm{CO}-(\mathrm{CH}_{2})_{2}-\mathrm{CH}_{3}\).
• 3-Methylbutan-2-one: A branched ketone: \((\mathrm{CH}_{3})_{2}\mathrm{CH}-\mathrm{CO}-\mathrm{CH}_{3}\).

Ketones are well known for their distinct smells and are often used in fragrances and solvents in industrial applications.

Aldehydes

Aldehydes feature a carbonyl group \((\mathrm{C}=\mathrm{O})\) situated at the end of a carbon chain, differentiating them from ketones. This positioning gives aldehydes their unique reactivity, often making them more susceptible to oxidation than ketones. With formula \(\mathrm{C}_{5}\mathrm{H}_{10}\mathrm{O}\), possible aldehydes include:

• Pentanal: A straightforward chain structure: \(\mathrm{CH}_{3}-(\mathrm{CH}_{2})_{3}-\mathrm{CHO}\).
• 2-Methylbutanal: A branched aldehyde: \((\mathrm{CH}_{3})_{2}\mathrm{CH}-\mathrm{CH}_{2}-\mathrm{CHO}\).
• 3-Methylbutanal: Another branched form: \(\mathrm{CH}_{3}-\mathrm{CH}(\mathrm{CH}_{3})-\mathrm{CH}_{2}-\mathrm{CHO}\).

Aldehydes are widely used in industries ranging from perfumery to polymer synthesis due to their reactive nature.

Esters

Esters are characterized by their distinctive fragrant aromas and are frequently found in essential oils and pheromones. Structurally, an ester contains a central carbon atom double-bonded to an oxygen (carbonyl group) and single-bonded to another oxygen, which is also bonded to an alkyl group. For an ester with \(\mathrm{C}_{4}\mathrm{H}_{8}\mathrm{O}_{2}\):

• Methyl propanoate: Its structure can be represented as \(\mathrm{CH}_{3}-\mathrm{CH}_{2}-\mathrm{COO}-\mathrm{CH}_{3}\).
• Ethyl acetate: A well-known solvent, \(\mathrm{CH}_{3}-\mathrm{COO}-\mathrm{CH}_{2}-\mathrm{CH}_{3}\).
• Propyl formate: Exhibiting another variation: \(\mathrm{HCOO}-\mathrm{CH}_{2}-\mathrm{CH}_{2}-\mathrm{CH}_{3}\).
• Isopropyl formate: Is structured as \(\mathrm{HCOO}-(\mathrm{CH}_{3})_{2}\mathrm{CH}\).

These esters are commonly used in flavorings and as intermediates in the manufacture of various products.

Ethers

Ethers are unique organic compounds characterized by an oxygen atom bonded to two alkyl or aryl groups. Typically, they have a general formula of \(\mathrm{R}-\mathrm{O}-\mathrm{R}'\), where \(\mathrm{R}\) and \(\mathrm{R}'\) are carbon-containing groups. Ethers are known for being excellent solvents, but have low reactivity due to the inert nature of the \(\mathrm{C}-\mathrm{O}-\mathrm{C}\) bond. For \(\mathrm{C}_{4}\mathrm{H}_{10}\mathrm{O}\), possible ether structures are:

• Diethyl ether: Commonly used as a solvent with the structure \(\mathrm{CH}_{3}-\mathrm{CH}_{2}-\mathrm{O}-\mathrm{CH}_{2}-\mathrm{CH}_{3}\).
• Methyl propyl ether: Represented as \(\mathrm{CH}_{3}-\mathrm{O}-\mathrm{CH}_{2}-\mathrm{CH}_{2}-\mathrm{CH}_{3}\).
• Ethyl methyl ether: Has the structure \(\mathrm{CH}_{3}-\mathrm{O}-\mathrm{CH}_{2}-\mathrm{CH}_{3}\).

These compounds are useful in a wide range of applications due to their low polarity and ability to dissolve both polar and nonpolar substances.