Organic Chemistry
6th Edition
ISBN: 9781936221349
Author: Marc Loudon, Jim Parise
Publisher: W. H. Freeman
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Question
Chapter 12, Problem 12.20P
Interpretation Introduction
(a)
Interpretation:
The peaks of
Concept introduction:
In mass spectrometry, an electron is lost to form a molecular ion. Two types of fragmentation occur. A stable molecular ion decomposes slowly and a peak with large relative abundance is detected in the mass spectrometer. If the molecular ion is unstable, it decomposes into several ions.
Interpretation Introduction
(b)
Interpretation:
The stable neutral molecule which can be lost to give the odd-electron ion is to be stated.
Concept introduction:
Mass spectroscopy is used to calculate mass to charge ratio of ions. Isotopic peak is also known as
Interpretation Introduction
(c)
Interpretation:
The mechanism for the origin of each fragment ion is to be stated.
Concept introduction:
Mass spectroscopy is used to calculate mass to charge ratio of ions. Isotopic peak is also known as
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Students have asked these similar questions
1 (c) 2-Methyl-3-pentanol reacts with PCC to form compound F.
(i) Draw the structure of F.
(ii) In the mass spectrum, identify the m/z value of the molecular ion peak for compound F.
(ii) Fragmentation of radical cation F exhibits two fragment ion peaks at m/z 57 and m/z 71. Propose
the structures of these two fragments.
(iv) Draw the resonance structure for each of the cation in (iii).
The 'H NMR spectrum of 1,2-dimethoxyethane (CH;OCH,CH2OCH3) recorded on a 300 MHz
NMR spectrometer consists of signals at 1017 Hz and 1065 Hz downfield from TMS. (a) Calculate
the chemical shift of each absorption. (b) At what frequency would each absorption occur if the
spectrum were recorded on a 500 MHz NMR spectrometer?
The mass spectrum of 2,2-dimethylpropane shows only a very weak molecular ion peak at m/z = 72. However, a large peak at m/z = 57 is seen. Suggest a possible structure of the fragment giving rise to this large peak and suggest a reason as to why this peak is so large.
Chapter 12 Solutions
Organic Chemistry
Ch. 12 - Prob. 12.1PCh. 12 - Prob. 12.2PCh. 12 - Prob. 12.3PCh. 12 - Prob. 12.4PCh. 12 - Prob. 12.5PCh. 12 - Prob. 12.6PCh. 12 - Prob. 12.7PCh. 12 - Prob. 12.8PCh. 12 - Prob. 12.9PCh. 12 - Prob. 12.10P
Ch. 12 - Prob. 12.11PCh. 12 - Prob. 12.12PCh. 12 - Prob. 12.13PCh. 12 - Prob. 12.14PCh. 12 - Prob. 12.15PCh. 12 - Prob. 12.16PCh. 12 - Prob. 12.17PCh. 12 - Prob. 12.18PCh. 12 - Prob. 12.19PCh. 12 - Prob. 12.20PCh. 12 - Prob. 12.21PCh. 12 - Prob. 12.22PCh. 12 - Prob. 12.23APCh. 12 - Prob. 12.24APCh. 12 - Prob. 12.25APCh. 12 - Prob. 12.26APCh. 12 - Prob. 12.27APCh. 12 - Prob. 12.28APCh. 12 - Prob. 12.29APCh. 12 - Prob. 12.30APCh. 12 - Prob. 12.31APCh. 12 - Prob. 12.32APCh. 12 - Prob. 12.33APCh. 12 - Prob. 12.34APCh. 12 - Prob. 12.35APCh. 12 - Prob. 12.36APCh. 12 - Prob. 12.37APCh. 12 - Prob. 12.38APCh. 12 - Prob. 12.39APCh. 12 - Prob. 12.40APCh. 12 - Prob. 12.41APCh. 12 - Prob. 12.42APCh. 12 - Prob. 12.43APCh. 12 - Prob. 12.44AP
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