Question

Draw a ketone that has the molecular formula \(\mathrm{C}_{4} \mathrm{H}_{8} \mathrm{O}\).

Short answer

The ketone that has the molecular formula \( C4H8O \) can be drawn as a carbonyl group with three Carbon atoms on one side and a single Carbon atom on the other. Each Carbon atom connected to the Carbonyl Carbon should also be connected to two Hydrogen atoms.

Step-by-step solution

Create Ketone Backbone

First, consider that ketones have a carbonyl group (C=O) with carbon chains on both sides, with the molecular structure as R-C=O-R'. This 'backbone' forms the essential structure of a ketone.

Add Carbon Atoms

Add 3 carbon atoms to one side of the carbonyl group and 1 carbon atom to the other side. All together, this will form a molecule with 4 carbon atoms, meeting the requirement of the molecular formula C4H8O.

Add Hydrogen Atoms

The carbonyl carbon and the carbon attached to the carbonyl oxygen each already have a hydrogen atom, because carbon tends to form four bonds, but these carbon atoms have only three so far. To complete a total of eight Hydrogen atoms, two are added to each remaining carbon. The complete structure should now satisfy the molecular formula C4H8O.

Key concepts

Ketone Structure

Ketones are a group of organic compounds that play a pivotal role in the field of organic chemistry. The structure of a ketone is characterized by a central carbon atom bonded to an oxygen atom through a double bond — this is commonly referred to as the carbonyl group. Flanking this carbonyl carbon are two carbon chains or groups which can vary in length and complexity.

In understanding ketone structures, one of the primary educational points is recognizing the importance of the carbonyl group placement. Unlike aldehydes, which have a carbonyl group at the end of the carbon chain, ketones have it within the chain. This distinction is crucial because it affects the chemical properties and reactivity of the molecule. By studying various ketones with different carbon chains, students can appreciate how such variations influence the physical and chemical behavior of these compounds.

Carbonyl Group

Central to understanding ketone structures is the concept of the carbonyl group, represented by the C=O structure. This functional group includes a carbon atom double-bonded to an oxygen atom. It's a feature that's found in several types of organic compounds, including aldehydes and carboxylic acids, in addition to ketones.

The carbonyl group is known for being highly reactive, which means it's often a site for chemical reactions. The double bond's nature makes the carbon atom electrophilic, which in layman's terms means it's prone to attack by nucleophiles, substances that donate electrons. This electrophilic character underlies many of the reactions involving ketones, such as their ability to form hydrates or undergo nucleophilic additions. Understanding the carbonyl group is fundamental to students for grasping how ketones interact in more complex chemical reactions.

Organic Chemistry

Organic chemistry is a sub-discipline of chemistry involving the scientific study of the structure, properties, composition, reactions, and synthesis of organic compounds and materials, which are defined by the presence of carbon atoms.

In the grand tapestry of organic chemistry, ketones are just one of many different classes of compounds, but they are significant due to their varied uses in different applications, from industrial to biological systems. For students, organic chemistry is often perceived as challenging due to the vast number of compounds and reactions. However, by breaking down study into smaller sections, such as understanding individual functional groups like the carbonyl group in ketones, students can build a more manageable and robust foundation of knowledge.

Molecular Formula C4H8O

When dissecting the molecular formula C4H8O, it indicates a compound with four carbon atoms (C), eight hydrogen atoms (H), and one oxygen atom (O). For students, interpreting molecular formulas is essential to visualize the structure of the compound it represents. In the case of a ketone with the molecular formula C4H8O, we must devise a structure that includes the carbonyl group along with the specified number of carbons and hydrogens.

This formula could correspond to several isomers, but since it's a ketone, the student must remember to include a carbonyl group within the carbon chain. The exercise guides through creating a backbone and then adding adequate hydrogen atoms to satisfy the valency of carbon, maintaining a focus on drawing a ketone specifically. This approach not only ensures the correct molecular makeup but also reinforces understanding of structural isomerism, a topic of considerable educational significance in organic chemistry.