Question

A compound, which is known as oil of bitter almonds is (a) acetaldehyde (b) acetone (c) acetophenone (d) benzaldehyde

Short answer

Answer: (d) Benzaldehyde

Step-by-step solution

1. Recall the properties and structure of oil of bitter almonds

Oil of bitter almonds has a characteristic odor and is obtained from almonds. It contains a significant amount of benzaldehyde, which is widely known for its almond-like fragrance.

2. Compare the options given

Compare the given compounds: Acetaldehyde, acetone, acetophenone, and benzaldehyde to determine which of these contains a significant almond-like odor.

3. Identify the compound as oil of bitter almonds

From the comparisons of each compound, benzaldehyde is the one with an almond-like odor, making it known as oil of bitter almonds.

4. Choose the correct option

Therefore, the correct option is (d) benzaldehyde, which is known as the oil of bitter almonds.

Key concepts

Benzaldehyde

Benzaldehyde is a colorless liquid with the empirical formula C₇H₆O and is best known for its characteristically pleasant almond-like odor. It occurs naturally in bitter almonds, as well as in other food products such as cherries and apricots. Chemically, benzaldehyde is the simplest aromatic aldehyde, and it is a key compound in organic syntheses, being a precursor for various fine chemicals. The identification of benzaldehyde, due to its distinctive fragrance, can be a straightforward sensory experience; however, in a laboratory setting, more precise analytical methods are used to confirm its presence. In the discussed exercise, the identification of oil of bitter almonds is directly associated with the recognition of benzaldehyde because of this well-known property.

Organic Chemistry

Organic Chemistry is a branch of science dedicated to the study of the structure, properties, composition, reactions, and synthesis of carbon-containing compounds. This field is vast, including both natural and synthetic compounds, and forms the basis for many applications in industries such as pharmaceuticals, petrochemicals, food, and textiles. Understanding the diversity of organic molecules and how they interact is fundamental. Taking the case of benzaldehyde, for example, one can appreciate its role within organic chemistry both in terms of its natural occurrence and varied uses in the synthesis of numerous other compounds. For students, grasping the principles of functional groups, such as the formyl group in aldehydes, is critical for navigating through the molecular complexity of organic compounds.

IIT JEE Chemistry Preparation

When preparing for competitive exams like the IIT JEE, an in-depth understanding of concepts in Chemistry is essential. Students must have a strong grasp of Organic Chemistry, as it is a significant portion of the JEE Chemistry syllabus. Effective preparation involves mastering the reactions, mechanisms, and the ability to identify and differentiate between compounds based on their functional groups or characteristic properties. Swift identification, like that of benzaldehyde's association with the oil of bitter almonds, is an example of the type of knowledge that could directly translate into exam success. To excel in this area, consistent practice with a variety of questions and familiarization with the basic concepts of carbon-based compounds is necessary.

Aldehyde Identification

Aldehydes are a class of organic compounds characterized by the presence of a carbonyl group (C=O) bonded to at least one hydrogen atom. Identification of aldehydes can be done through various methods. In qualitative analysis, chemical tests such as the Tollens' test (silver mirror test), Fehling's test, and Schiff's test are performed to detect the presence of the aldehyde functional group. In instrumental analysis, techniques like mass spectrometry, infrared spectroscopy, and nuclear magnetic resonance (NMR) are employed for more rigorous analysis. In everyday scenarios or in introductory organic chemistry content, simpler cues such as the distinctive odor of benzaldehyde can be used for identification, as highlighted in the textbook exercise, where its olfactory trait distinctly marks it as oil of bitter almonds.