(a)
Interpretation:
The
Concept introduction:
Spectroscopy method is used to identify the structure of the substance. The mass spectroscopy is used to determine the molecular mass. In the mass spectrum, the molecular ion is the most important peak. The
(b)
Interpretation:
The reason as to why the mass spectrum of methyl isobutyl ether does not show a peak due to inductive cleavage, in contrast to the mass spectrum of di-sec-butyl-ether is to be stated.
Concept introduction:
Spectroscopy method is used to identify the structure of the substance. The mass spectroscopy is used to determine the molecular mass. In the mass spectrum, the molecular ion is the most important peak. The
(c)
Interpretation:
The major difference that is expected when comparing the
Concept introduction:
The mass spectroscopy is used to determine the molecular mass. In the mass spectrum, the molecular ion is the most important peak. The
Want to see the full answer?
Check out a sample textbook solutionChapter 12 Solutions
Organic Chemistry
- Write molecular formulas for compounds that show the following molecular ions in their high-resolution mass spectra, assuming that C, H, N, and O might be present. The exact atomic masses are: 1.007 83 (1H), 12.000 00 (12C), 14.003 07 (14N), 15.994 91 (16O). (a) M+=98.0844 (b) M+=123.0320arrow_forwardFollowing is the mass spectrum of bromocyclopentane. The molecular ion m/z 148 is of such low intensity that it does not appear in this spectrum. Assign structural formulas for the cations of m/z 69 and 41.arrow_forwardThe mass spectrum of 1-ethyl-1-methylcyclohexane shows many fragments, with two in very large abundance. Kne appears af m/z=111 and the other appears at m/z=97. Identify the structure of each of these fragments.arrow_forward
- A low-resolution mass spectrum of the neurotransmitter dopamine gave a molecular ion at m/z = 153. Two possible molecular formulas for this molecular ion are C8H11NO2 and C7H11N3O. A high-resolution mass spectrum provided an exact mass at 153.0680. Which of the possible molecular formulas is the correct one?arrow_forwardThe mass spectrum of n-octane shows a prominent molecular ion peak (m>z 114). There is also a large peak at m>z 57,but it is not the base peak. The mass spectrum of 3,4-dimethylhexane shows a smaller molecular ion, and the peak atmass 57 is the base peak. Explain these trends in abundance of the molecular ions and the ions at mass 57, and predict theintensities of the peaks at masses 57 and 114 in the spectrum of 2,2,3,3-tetramethylbutane.arrow_forwardThe mass spectrum of 1-ethyl-1-methylcyclohexane shows many fragments, with two in very large abundance. One appears at m/z = 111 and the other appears at m/z = 97. Determine the identity and structure of each of these fragmentsarrow_forward
- A mass spectrum shows significant peaks at m>z = 87, 115, 140, and 143. Which of the following compounds is responsible for that mass spectrum?arrow_forwardWhich of the following compounds appears in the mass spectrum to have a baseline peak at m/z=43, indicating the reason OH B OH OH C Darrow_forwardAssigning Possible Structures to Fragments in a Mass Spectrum The mass spectrum of 2,3-dimethylpentane [(CH3)2CHCH(CH3)CH2CH3] shows fragments at m/z = 85 and 71. Propose possible structures for the ions that give rise to these peaks.arrow_forward
- The 1H NMR spectrum of 1,2-dimethoxyethane (CH3OCH2CH2OCH3) 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?arrow_forwardThe mass spectrum of compound B is shown below. 100 180 80 181 77 В 182 20 104 25 50 75 100 125 150 175 200 m/z (i) Identify the molecular ion peak of compound B. (ii) Explain the peak at m/z 182 in terms of intensity. (iii) Explain the formation of the other labelled fragments (m/z 180, 104 and 77). Relative Intensityarrow_forwardLabel the molecular ion, the base peak, and the M + 1 peak in the mass spectrum of pentane (C5H12).arrow_forward
- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning