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Ch.12 Introduction to Organic Chemistry: Alkanes
McMurry - Fundamentals of GOB 8th Edition
McMurry8th EditionFundamentals of GOBISBN: 9780134015187Not the one you use?Change textbook
Chapter 12, Problem 10a

Are the pairs of compounds shown below the same molecule, isomers, or different molecules?
a.

Verified step by step guidance
1
Examine the structural formulas of the two compounds carefully. Look for differences in the arrangement of atoms, connectivity, or functional groups.
Determine if the compounds have the same molecular formula. If they do not, they are different molecules. If they do, proceed to the next step.
Check the connectivity of the atoms in each compound. If the atoms are connected in the same way, the compounds are the same molecule. If the connectivity differs, proceed to the next step.
Analyze the spatial arrangement of the atoms (stereochemistry). If the connectivity is the same but the spatial arrangement differs (e.g., cis/trans isomers or enantiomers), the compounds are isomers.
Conclude whether the compounds are the same molecule, isomers, or different molecules based on the analysis of molecular formula, connectivity, and stereochemistry.

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Molecular Structure

Molecular structure refers to the arrangement of atoms within a molecule, including the types of atoms, their connectivity, and the spatial orientation. Understanding molecular structure is crucial for determining whether two compounds are identical, isomers, or entirely different molecules. For example, the same molecular formula can represent different structures, leading to different chemical properties.
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Isomerism

Isomerism is a phenomenon where two or more compounds have the same molecular formula but differ in the arrangement of atoms. Isomers can be classified into structural isomers, which differ in connectivity, and stereoisomers, which differ in spatial orientation. Recognizing isomers is essential for understanding how compounds can exhibit different chemical behaviors despite having the same composition.
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Chemical Identity

Chemical identity refers to the unique characteristics that define a specific compound, including its molecular formula, structure, and properties. To determine if two compounds are the same molecule or different, one must analyze their chemical identities. This concept is fundamental in chemistry, as it helps distinguish between compounds that may appear similar but have distinct chemical behaviors.
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