For the mass spectrum of B r 2 , the molecular species give peaks at m/Z ratios of 158, 160, and 162 are needed to be determined. Concept introduction: Mass spectroscopy: It is a form of spectroscopic technique which is used for the elucidation of the molecules, depending upon the mass of the molecule. Parent ion peak: It is defined as the prominent peak in the mass spectrum of the molecule which represents the not fragmented molecular ion in the given molecule with greater m/z value. Base peak: It is the tallest peak in the spectrum. B r 2 ionize to form positive ions, B r 2 + a n d B r + . Elements present in B r 2 are 79 B r a n d 81 B r .
For the mass spectrum of B r 2 , the molecular species give peaks at m/Z ratios of 158, 160, and 162 are needed to be determined. Concept introduction: Mass spectroscopy: It is a form of spectroscopic technique which is used for the elucidation of the molecules, depending upon the mass of the molecule. Parent ion peak: It is defined as the prominent peak in the mass spectrum of the molecule which represents the not fragmented molecular ion in the given molecule with greater m/z value. Base peak: It is the tallest peak in the spectrum. B r 2 ionize to form positive ions, B r 2 + a n d B r + . Elements present in B r 2 are 79 B r a n d 81 B r .
Interpretation: For the mass spectrum of Br2, the molecular species give peaks at m/Z ratios of 158, 160, and 162 are needed to be determined.
Concept introduction:
Mass spectroscopy: It is a form of spectroscopic technique which is used for the elucidation of the molecules, depending upon the mass of the molecule.
Parent ion peak: It is defined as the prominent peak in the mass spectrum of the molecule which represents the not fragmented molecular ion in the given molecule with greater m/z value.
Base peak: It is the tallest peak in the spectrum.
Br2 ionize to form positive ions, Br2+andBr+.
Elements present in Br2 are 79Brand81Br.
(b)
Interpretation Introduction
Interpretation:
For the mass spectrum of Br2, the relative intensities of the peaks has to be explained.
Concept introduction:
Mass spectroscopy: It is a form of spectroscopic technique which is used for the elucidation of the molecules, depending upon the mass of the molecule.
Parent ion peak: It is defined as the prominent peak in the mass spectrum of the molecule which represents the not fragmented molecular ion in the given molecule with greater m/z value.
Base peak: It is the tallest peak in the spectrum.
Bromine has two naturally occurring isotopes, 79Br , abundance 50.52%, and 81Br, abundance 49.48%. The most stable form of bromine under standard conditions is as the diatomic molecule, Br2 . In a mass spectrum of bromine, at what m/z values would you expect to see peaks and what would you expect the relative height of the peaks to be? What species would account for each peak? Explain.
The highest mass peaks in the mass spectrum of Br2 occur at m/Z 158, 160, and 162. The ratio of intensities of these peaks is approximately 1:2:1. Bromine has two stable isotopes,79Br (50.7% abundance) and 81Br (49.3% abundance).
question: What molecular species gives rise to each of these peaks? (Include the mass numbers of the isotopes in your answers.)
2clar
ISTRY EXAM
A Chemistry student performed an experiment on the preparation and identification of an ester. He was given
solutions of a carboxylic acid and an alcohol. He then prepared the ester as per laboratory instruction and
identified the odour of the ester as a pear flavour.
A carboxylic acid has empirical formula CH,O, and its structure is determined by using various spectroscopic
techniques.
(a) The mass spectrum for this carboxylic acid molecule is given below.
100-
80-
60-
relative
intensity
40-
20-
10 15 20 25 30 35 40 45 50 55 60 65 70 75
mass/charge (m/e)
(i) State the relative molecular mass of this molecule; hence determine its molecular formula.
(ii) Draw the structural formula of the carboxylic acid and give its systematic name.
ark
(b) Use the information provided by its Infrared spectrum below to answer the following questions
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Author:Steven D. Gammon, Ebbing, Darrell Ebbing, Steven D., Darrell; Gammon, Darrell Ebbing; Steven D. Gammon, Darrell D.; Gammon, Ebbing; Steven D. Gammon; Darrell
Author:Steven D. Gammon, Ebbing, Darrell Ebbing, Steven D., Darrell; Gammon, Darrell Ebbing; Steven D. Gammon, Darrell D.; Gammon, Ebbing; Steven D. Gammon; Darrell