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Mass Spectrometry

Mass Spectrometry is the study of the spectra of masses in order to determine not only the elemental composition but also the chemical structures of molecules. The mass spectrometer, the instrument which generates the spectra, is comprised of three components: ionizer, mass analyzer and detector. Generating the mass spectrum of a molecule first involves using the ionizer to ionize the incoming molecules. Then, eventually, the ionized molecules will break apart to form ionized molecular fragments, where the mass analyzer sorts them out based on their mass-to-charge ratio. These fragments are subsequently processed by the detector into a mass spectrum based on the relative abundances of these different ionic molecular fragments. Once the spectrum has been generated by the spectrometer, the individual molecular fragments can then be identified by its specific mass-to-charge ratio and its characteristic fragmentation pattern. When analyzing the spectrum, the peak furthest to the right always represents the ionized molecule which has not broken apart; while, every peak to the left of it represents the fragments it has broken up into. For the molecule n-decane, the peak furthest to the right will have a mass-to-charge ratio of 142. The ions detected to the left of this peak correspond to different fragments that differ by 14 mass units, which are formed by the cleaving of the adjacent CH_2 groups. Thus, understanding how to analyze a mass spectrum is crucial for identifying specific molecules.

Experimental Procedure for RGA Mass Spectrometer

See the attached file. Experimental Procedure for RGA Mass Spectrometer. Information Ionizer Setup Ionization Energy: 35V Electron Emission: 0.5mA Ion Energy: Low 8eV Focus Plate Voltage: 45 Scan/Log Setup Initial [Mass] : 120[amu] Steps [steps/amu]: 25 Final [Mass] ; 145[amu] Disable After: 1[scan] Problems. X

ICP-MS

Write a brief account on the use of ICP-MS. Describe the Factors influencing the sensitivity of the elements being measured and potential use of ICP-MS besides total elemental analysis.

Mass spectrum

For the spectrum attached in document, I need help with calculating a possible molecular formula for this compound. This compound contains C, H, and Br. Can you also show your work, I want to check my work. Thanks.

What is Mass Spectrometry?

Mass spectrometry (MS) makes use of the motion of ions in electric and magnetic fields in order to sort them according to their mass-to-charge ratios. Thus, MS is an analytic technique by which chemical substances are identified by the sorting of gaseous ions in electric and magnetic fields. The instruments used in these studies

Mass Spectrometer

A mass spectrometer is a device that uses a magnetic field to sort atoms by mass. In this device, atoms whose masses are to be determined are ionized by stripping off one electron. They are then sent through a velocity selector that selects ions only with specific speed V, and these ions are sent into a region of space filled