**Model 3: Ionization and Fragmentation**Most mass spectrometers accelerate a molecule by first turning it into an ion, then using an electric field to accelerate it toward the detector. During standard ionization, a molecule loses one electron, the electron that is easiest to remove. The following is a hierarchy of electrons from easiest to hardest to remove:- Electron in a lone pair (easiest)- Electron that is part of a double bond (pi bond)- Electron in a single bond (hardest)Knocking off an electron to make a +1 ion can be a harsh process. This harsh treatment often results in a broken bond, generating two smaller pieces, a +1 ion and a neutral fragment. *(Note that only the ion is accelerated and detected.)***Critical Thinking Questions**6. If acetone is ionized, which electron is most likely to be knocked off? Replace this electron with a + (to indicate the missing electron) on the structure of acetone: ![Acetone Structure Diagram](Your_Diagram_Link)7. The ion you drew above is called the “molecular ion” of acetone. It is identical to the original molecule except that it is missing an electron, has a + charge, and can be accelerated by the mass spectrometer. What is the weight (in amu) of the molecular ion of acetone? (Report only two significant figures, e.g., XX amu)**Model 4: Mass Spectrum of Acetone**The mass spectrum of acetone is a tally of the number of ions of each mass (m/z) that hit the detector when a large number of acetone molecules are run through the mass spectrometer. The peak intensity (peak height) tells you the relative number of ions of that weight that hit the detector.| m/z | Peak Intensity ||------|----------------|| 14.0 | 2.9 || 15.0 | 23.1 || 26.0 | 3.5 || 27.0 | 5.7 || 29.0 | 3.1 || 38.0 | 2.2 || 39.0 | 4.2 || 41.0 | 2.0 || 42.0 | 9.1 || 43.0 **Mass Spectrometry: Understanding Base Peak vs. Molecular Ion****Question 10:**- **Inquiry:** Determine the weight (m/z) and intensity (height) of the most common ion detected in a mass spectrometry experiment.- **Note:** The tallest peak in the mass spectrum represents this ion.**Memorization Task L2.1: Base Peak vs. Molecular Ion**- **Warning:** The [M]⁺ peak (molecular ion) is often *not* the same as the base peak (largest peak).- **Base Peak Identification:** This is the largest peak, conventionally set to 100.- **Molecular Ion Identification:** Understanding the analyte's structure (e.g., acetone) aids in identifying the [M]⁺ peak. Identifying the [M]⁺ on unknowns' spectra is challenging and forms a key focus.**Question 11:**- **Inquiry:** Consider if the base and [M]⁺ peaks are the same for acetone's spectrum as shown previously.**Question 12:**- **Inquiry:** Determine the size (in amu) of the neutral fragment lost to result in a base peak at m/z = 43. **Sub-questions:** a. Identify the atoms' combination that accounts for the m/z = 43 peak. b. Explain why the m/z = 43 peak is denoted as the [M-15]⁺ peak. c. Using this naming method, name the mass spectrum peak at m/z = 15.**Question 13:**- **Information:** Major peaks lighter than the molecular ion in a spectrum are fragment peaks.- **Task:** Draw an ion that could account for the [M-15]⁺ peak in acetone’s mass spectrum. This exercise enhances understanding of peak identification in mass spectrometry, emphasizing differentiation between base and molecular ions.

Since you have posted multiple questions, according to guidelines I am solving first two which are…

6. 7. If acetone is ionized, which electron is most likely to be knocked off? Replace this electron with a + (to indicate the missing electron) on the structure of acetone → :O: The ion you drew above is called the "molecular ion" of acetone. It is identical to the original molecule except that it is missing an electron, has a + charge, and can be accelerated by the mass spectrometer. What is the weight (in amu) of the molecular ion of acetone? (report only two significant figures, e.g., XX amu)

6. 7. If acetone is ionized, which electron is most likely to be knocked off? Replace this electron with a + (to indicate the missing electron) on the structure of acetone → :O: The ion you drew above is called the "molecular ion" of acetone. It is identical to the original molecule except that it is missing an electron, has a + charge, and can be accelerated by the mass spectrometer. What is the weight (in amu) of the molecular ion of acetone? (report only two significant figures, e.g., XX amu)

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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