Question

Give the structural formula for (a) an aldehyde that is an isomer of acetone, (b) an ether that is an isomer of 1 -propanol.

Short answer

(a) The aldehyde isomer of acetone has the structural formula \( H_{3}COCH_{2} \). (b) The ether isomer of 1-propanol has the structural formula \( CH_3OCH_2CH_3 \).

Step-by-step solution

(a) Aldehyde Isomer of Acetone

Step 1: Write the molecular formula of acetone Acetone is a ketone with the formula C3H6O Step 2: Determine the isomer with an aldehyde functional group With the same molecular formula as acetone, an aldehyde isomer will be formed by replacing the ketone functional group (C=O) with an aldehyde functional group (HC=O) within the carbon chain. Step 3: Draw the structural formula of the aldehyde isomer The structural formula for the aldehyde isomer of acetone is \( C_3H_6O \) and with a functional aldehyde group: \(H_{3}COCH_{2} \)

(b) Ether Isomer of 1-Propanol

Step 1: Write the molecular formula of 1-propanol 1-propanol is an alcohol with the formula C3H8O Step 2: Determine the isomer with an ether functional group Keep the same molecular formula as 1-propanol, but this time, find another molecule that has an ether functional group (R-O-R'). Step 3: Draw the structural formula of the ether isomer The structural formula for the ether isomer of 1-propanol is \( C_3H_8O \) and with an ether functional group: \(CH_3OCH_2CH_3 \)

Key concepts

Aldehydes

Aldehydes are a type of organic compound known for having a distinctively simple structure that includes the functional group HC=O, also known as the aldehyde group.
This group consists of a carbon atom bonded to a hydrogen atom and double-bonded to oxygen.
An aldehyde is an organic compound containing the formyl group, which is represented as \(-CHO\).In the realm of isomerism, an important aspect involves identifying how different compounds

• Can have the same molecular formula yet distinct structural arrangements.
• For example, acetone's molecular formula is \(C_3H_6O\).
• The aldehyde isomer of acetone also has the formula \(C_3H_6O\), but a different structure.

It involves substituting the ketone group (C=O) with the aldehyde group (HC=O) within the carbon chain, keeping the number of carbons consistent. In summary, aldehydes contribute significantly to isomerism by showcasing the diversity of molecules that can result even though they stem from the same set of atoms.

Ethers

Ethers are a class of organic compounds that can be recognized by their distinctive ether group,
depicted as (R-O-R'), where R and R' represent various carbon-containing groups.
This functional group consists of an oxygen atom connected by single bonds to two alkyl
or aryl groups, forming a structure that is different from alcohols.Ethers demonstrate how molecular formula resemblance can coexist with structural diversity.

• For instance, 1-propanol (\(C_3H_8O\)) shares its molecular formula with an ether isomer.
• This involves aligning the molecule to exhibit the ether linkage rather than the alcohol (-OH) group.
• The result is an ether structure where an oxygen atom connects two alkyl groups \(CH_3OCH_2CH_3\).

Understanding ethers elevates comprehension of organic chemistry by emphasizing functional group variance and its impact on molecular identity.

Structural Formula

The structural formula of a compound is essential for visualizing the arrangement
of atoms within a molecule. Unlike the molecular formula, which provides the count
of each type of atom, the structural formula illustrates the connections and organization of atoms, offering insights that basic formulas cannot provide.Aldehydes and ethers serve as exemplary cases where structural formulas reveal distinctions that

• Cannot be discerned from molecular formulas alone.
• An aldehyde isomer of acetone (\(C_3H_6O\)) illustrates this by reorganizing the moleculeinto a form including a HC=O group compared to the acetone's double-bonded carbonyl group (C=O).
• Similarly, the ether isomer of 1-propanol (\(CH_3OCH_2CH_3\)) showcases a structuralrearrangement where the oxygen atom bridges two carbon chains.

Structural formulas thereby impart clarity to the internal makeup and differences between molecules that simple molecular formulas might obscure.

Functional Groups

Functional groups are critical in organic chemistry as they define the specific set of atoms
that determine a molecule's characteristic reactions and properties. They are pivotal to naming and
distinguishing different organic compounds. In the context of isomerism demonstrated by aldehydes and ethers,

• The identification and comprehension of functional groups illuminates the differences between these compounds.
• An aldehyde group is characterized by a carbon double-bonded to oxygen and single-bonded to hydrogen (HC=O), altering the molecular dynamics compared to a ketone.
• Conversely, an ether group features an oxygen atom bonded to two different carbon groups (R-O-R'), distinguishing it from alcohols which have hydroxyl groups (-OH).

The strategic placement and type of functional group within a molecule determine both behavior and identity, making them a focal point for understanding chemical properties and reactivity.