Question

Boiling point of acetaldehyde is approx (A) \(20^{\circ} \mathrm{C}\) (B) \(40^{\circ} \mathrm{C}\) (C) \(72^{\circ} \mathrm{C}\) (D) \(100^{\circ} \mathrm{C}\)

Short answer

The boiling point of acetaldehyde is approximately \(20^{\circ}\mathrm{C}\). So, the correct answer is (A) \(20^{\circ}\mathrm{C}\).

Step-by-step solution

Look up the boiling point of acetaldehyde

Look up the boiling point of acetaldehyde from a reliable data source, such as a textbook, chemistry table, or online source. Always ensure that your source is credible and accurate.

Compare the given options to the published boiling point

Once you have found the boiling point of acetaldehyde, compare that value to the four options provided: (A) \(20^{\circ}\mathrm{C}\) (B) \(40^{\circ}\mathrm{C}\) (C) \(72^{\circ}\mathrm{C}\) (D) \(100^{\circ}\mathrm{C}\)

Choose the correct answer

After comparing the provided options to the boiling point of acetaldehyde found in your data source, select the option that most closely matches the correct boiling point. The choice will be the answer to the exercise. After consulting the data source, we find out that the boiling point of acetaldehyde is approximately \(20^{\circ}\mathrm{C}\). Thus, the correct answer is: (A) \(20^{\circ}\mathrm{C}\)

Key concepts

Acetaldehyde

Acetaldehyde is a simple organic compound with the formula \( ext{CH}_3 ext{CHO}\). It is a colorless, flammable liquid that has a sharp, fruity odor. In the field of organic chemistry, acetaldehyde is known as an important intermediate. It occurs naturally in coffee, bread, and ripe fruits, and also plays a significant role in the metabolism of alcohol in the human body.
In industrial applications, acetaldehyde is used predominantly in the production of acetic acid, perfumes, and flavoring agents. Understanding its properties is crucial for dealing with it safely in a lab or industrial setting. One critical property of acetaldehyde is its low boiling point, approximately \(20^{ ext{\circ}} ext{C}\), which implies that it can easily transition to a gas at room temperature. Hence, it requires careful handling to prevent accidental inhalation or explosive scenarios.
Recognizing its boiling point is essential in scenarios such as distillation, where separating components based on boiling points is fundamental. It also acts as a reference point in various chemical reactions where accurate temperature control is vital. Knowing about acetaldehyde's tendency to polymerize in the presence of an acid catalyst is equally important, emphasizing safety and accuracy in chemical handling.

Organic Chemistry Problems

Organic chemistry problems often revolve around understanding molecular structures, reactions, and properties of organic compounds. Acetaldehyde is a classic example used in these problems because it is reactive and participates in a variety of chemical reactions.
When solving these problems, it's vital to have a systematic approach:

• Identify the functional groups in the compound—Acetaldehyde contains an aldehyde group.
• Consider the properties—For acetaldehyde, low boiling point and ability to engage in addition reactions are vital.
• Analyze potential reactions and mechanisms—Acetaldehyde can undergo oxidation to form acetic acid or reduction to ethanol.

These steps help predict how acetaldehyde would react under different conditions, thus solving the organic chemistry problems effectively. Moreover, organic chemistry often requires the understanding of intermolecular forces, such as hydrogen bonding, which acetaldehyde lacks compared to alcohols and carboxylic acids, leading to its relatively lower boiling point.
Another common problem involves comparing physical properties based on molecular structure. Recognizing the influences of molecular size, shape, and functional groups on physical properties like boiling points is a common test item in organic chemistry, making acetaldehyde a perfect example used in problem questions.

JEE Preparation

JEE (Joint Entrance Examination) preparation often includes a thorough understanding of chemistry, particularly organic chemistry, due to its significant weight in the examination. Acetaldehyde and compounds like it frequently appear in chemistry questions as they represent fundamental concepts that students need to comprehend.
When preparing for the JEE, students should focus on several key areas:

• Understand the structure and nomenclature of organic compounds.
• Learn about different organic reactions and their mechanisms.
• Master the concepts of isomerism and functional groups, like the aldehyde group in acetaldehyde.

To solve questions related to boiling points, like the one concerning acetaldehyde, students should consult reliable data sources and practice discerning the correct information quickly. Recognizing how intermolecular forces affect boiling points, such as the lack of hydrogen bonding in acetaldehyde, can be crucial.
This knowledge extends beyond acetaldehyde to many other compounds in organic chemistry, aiding in a more comprehensive understanding of the subject, which is necessary for excelling in the JEE. Thus, focusing on understanding the underlying principles in organic chemistry problems is essential for effective JEE preparation. Practice with past papers and mock tests reinforce these principles, helping students gain confidence and precision.