Question

The compound having only \(1^{\circ}\) hydrogen is (A) Methyl methanoate (B) Neopentane (C) Methoxy methane (D) Isopentane

Short answer

The compound with only primary (1°) hydrogens is (C) Methoxy methane (CH3OCH3) which has 6 primary hydrogens.

Step-by-step solution

Identify the structures of the given compounds

First, let's identify the structures of the given compounds: (A) Methyl methanoate: HCOOCH3 (B) Neopentane: (CH3)4C (C) Methoxy methane: CH3OCH3 (D) Isopentane: (CH3)2CHCH2CH3

Find the primary hydrogens in each compound

Now, let's find the primary hydrogens in each compound: (A) Methyl methanoate: HCOOCH3 - Primary hydrogens: 3 (attached to the CH3 group). (B) Neopentane: (CH3)4C - Primary hydrogens: 0 (since the central carbon is attached to four other carbon atoms, all the hydrogens will be 3°). (C) Methoxy methane: CH3OCH3 - Primary hydrogens: 6 (3 hydrogens on each CH3 group, and both carbons are primary). (D) Isopentane: (CH3)2CHCH2CH3 - Primary hydrogens: 8 (3 hydrogens on each of the two terminal CH3 groups, 2 hydrogens on the CH2 group, and none on the central CH).

Choose the correct answer

Now that we've determined the primary hydrogens in each compound, we can see that the correct answer is: (C) Methoxy methane (CH3OCH3), with 6 primary hydrogens.

Key concepts

Understanding Organic Chemistry

Organic chemistry is the study of carbon-containing compounds and their properties, structures, and reactions. It plays a vital role in the development of various chemicals essential to industry and life, such as plastics, pharmaceuticals, and fuels. One of the critical first steps to mastering organic chemistry is understanding the various types of hydrogens - primary (1°), secondary (2°), tertiary (3°), and quaternary (4°) - because they can greatly influence a molecule's reactivity and properties.

In organic molecules, primary hydrogens are attached to a carbon atom that is also bonded to only one other carbon atom. These hydrogens are often involved in chemical reactions such as substitutions or eliminations. Recognizing the type of hydrogens in a hydrocarbon structure is essential for predicting the outcomes of chemical reactions, making it a foundational concept in organic chemistry education and relevant competitive exams like the JEE Main and Advanced.

The Significance of JEE MAIN AND ADVANCED in Mastering Organic Chemistry

The Joint Entrance Examination (JEE) Main and Advanced are crucial in assessing a student's grasp of core science subjects, including organic chemistry, for admission into prestigious engineering institutes in India. Questions related to hydrocarbon structures and the identification of primary hydrogens are typical because they test students' understanding of organic compounds' fundamental architecture.

To excel in these exams, students need to have a deep understanding of not only the theoretical aspects but also practical application. Questions like the one asking to identify the compound having only primary hydrogens test conceptual clarity and the ability to apply this knowledge quickly and accurately. For JEE aspirants, being adept at these concepts could mean the difference between an average score and an outstanding one.

Unravelling Hydrocarbon Structures

Hydrocarbon structures consist of hydrogen atoms bonded to a carbon skeleton. These structures come in various forms such as alkanes, alkenes, alkynes, and aromatic hydrocarbons, each with unique characteristics and reactivities. Primary hydrogens in these structures are those bonded to a carbon that is connected to only one other carbon. Understanding these structures is pivotal in predicting the behavior of organic compounds during chemical reactions.

For instance, in the reaction mechanisms, primary hydrogens are more likely to be involved in certain types of reactions, such as free-radical halogenation, than secondary or tertiary hydrogens. Accurate predictions require a clear understanding of these structural differences. Therefore, studying hydrocarbon structures forms an essential part of the curriculum for JEE Main and Advanced and serves as an invaluable tool for any student aspiring to make strides in organic chemistry.