Principles of Instrumental Analysis
Principles of Instrumental Analysis
7th Edition
ISBN: 9781305577213
Author: Douglas A. Skoog, F. James Holler, Stanley R. Crouch
Publisher: Cengage Learning
Question
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Chapter 19, Problem 19.21QAP
Interpretation Introduction

(a)

Interpretation:

The appearance of the high-resolution 13C spectrum of (proton decoupled) methyl formate is to be stated.

Concept introduction:

The whole signals that appear in the proton decoupled 13C NMR spectrum are a singlet. Due to several reasons, the carbon atoms are do not coupled with the adjacent carbon atom. The only condition to form 13C13C bond is that two 13C atoms must be adjacent to each other. It is almost impossible for two 13C nuclei to be adjacent to each other because the presence 13C atoms in nature are less abundant and also the 13C nuclei do not couple with the 12C nuclei because of zero spin quantum number.

Interpretation Introduction

(b)

Interpretation:

The appearance of the high-resolution 13C spectrum of (proton decoupled) acetaldehyde is to be stated.

Concept introduction:

The whole signals that appear in the proton decoupled 13C NMR spectrum are singlet in nature. Due to several reasons, the carbon atoms are do not coupled with the adjacent carbon atom. The only condition to form 13C13C bond is that two 13C atoms must be adjacent to each other. It is almost impossible for two 13C nuclei to be adjacent to each other because the presence 13C atoms in nature are less abundant and also the 13C nuclei do not couple with the 12C nuclei because of zero spin quantum number.

Interpretation Introduction

(c)

Interpretation:

The appearance of the high-resolution 13C spectrum of (proton decoupled) acetone is to be stated.

Concept introduction:

The whole signals that appear in the proton decoupled 13C NMR spectrum are singlet in nature. Due to several reasons, the carbon atoms are do not coupled with the adjacent carbon atom. The only condition to form 13C13C bond is that two 13C atoms must be adjacent to each other. It is almost impossible for two 13C nuclei to be adjacent to each other because the presence 13C atoms in nature are less abundant and also the 13C nuclei do not couple with the 12C nuclei because of zero spin quantum number.

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