Dr. Laurie Starkey
Mass Spectrometry
Slide Duration:Table of Contents
21m 9s
- Intro0:00
- Sample Reagent Table0:11
- Reagent Table Overview0:12
- Calculate Moles of 2-bromoaniline6:44
- Calculate Molar Amounts of Each Reagent9:20
- Calculate Mole of NaNO₂9:21
- Calculate Moles of KI10:33
- Identify the Limiting Reagent11:17
- Which Reagent is the Limiting Reagent?11:18
- Calculate Molar Equivalents13:37
- Molar Equivalents13:38
- Calculate Theoretical Yield16:40
- Theoretical Yield16:41
- Calculate Actual Yield (%Yield)18:30
- Actual Yield (%Yield)18:31
16m 10s
- Intro0:00
- Definition of a Melting Point (mp)0:04
- Definition of a Melting Point (mp)0:05
- Solid Samples Melt Gradually1:49
- Recording Range of Melting Temperature2:04
- Melting Point Theory3:14
- Melting Point Theory3:15
- Effects of Impurities on a Melting Point3:57
- Effects of Impurities on a Melting Point3:58
- Special Exception: Eutectic Mixtures5:09
- Freezing Point Depression by Solutes5:39
- Melting Point Uses6:19
- Solid Compound6:20
- Determine Purity of a Sample6:42
- Identify an Unknown Solid7:06
- Recording a Melting Point9:03
- Pack 1-3 mm of Dry Powder in MP Tube9:04
- Slowly Heat Sample9:55
- Record Temperature at First Sign of Melting10:33
- Record Temperature When Last Crystal Disappears11:26
- Discard MP Tube in Glass Waste11:32
- Determine Approximate MP11:42
- Tips, Tricks and Warnings12:28
- Use Small, Tightly Packed Sample12:29
- Be Sure MP Apparatus is Cool12:45
- Never Reuse a MP Tube13:16
- Sample May Decompose13:30
- If Pure Melting Point (MP) Doesn't Match Literature14:20
8m 17s
- Intro0:00
- Melting Point Tubes0:40
- Melting Point Apparatus3:42
- Recording a melting Point5:50
22m
- Intro0:00
- Crystallization to Purify a Solid0:10
- Crude Solid0:11
- Hot Solution0:20
- Crystals1:09
- Supernatant Liquid1:20
- Theory of Crystallization2:34
- Theory of Crystallization2:35
- Analysis and Obtaining a Second Crop3:40
- Crystals → Melting Point, TLC3:41
- Supernatant Liquid → Crude Solid → Pure Solid4:18
- Crystallize Again → Pure Solid (2nd Crop)4:32
- Choosing a Solvent5:19
- 1. Product is Very Soluble at High Temperatures5:20
- 2. Product has Low Solubility at Low Temperatures6:00
- 3. Impurities are Soluble at All Temperatures6:16
- Check Handbooks for Suitable Solvents7:33
- Why Isn't This Dissolving?!8:46
- If Solid Remains When Solution is Hot8:47
- Still Not Dissolved in Hot Solvent?10:18
- Where Are My Crystals?!12:23
- If No Crystals Form When Solution is Cooled12:24
- Still No Crystals?14:59
- Tips, Tricks and Warnings16:26
- Always Use a Boiling Chip or Stick!16:27
- Use Charcoal to Remove Colored Impurities16:52
- Solvent Pairs May Be Used18:23
- Product May 'Oil Out'20:11
19m 7s
- Intro0:00
- Step 1: Dissolving the Solute in the Solvent0:12
- Hot Filtration6:33
- Step 2: Cooling the Solution8:01
- Step 3: Filtering the Crystals12:08
- Step 4: Removing & Drying the Crystals16:10
25m 54s
- Intro0:00
- Distillation: Purify a Liquid0:04
- Simple Distillation0:05
- Fractional Distillation0:55
- Theory of Distillation1:04
- Theory of Distillation1:05
- Vapor Pressure and Volatility1:52
- Vapor Pressure1:53
- Volatile Liquid2:28
- Less Volatile Liquid3:09
- Vapor Pressure vs. Boiling Point4:03
- Vapor Pressure vs. Boiling Point4:04
- Increasing Vapor Pressure4:38
- The Purpose of Boiling Chips6:46
- The Purpose of Boiling Chips6:47
- Homogeneous Mixtures of Liquids9:24
- Dalton's Law9:25
- Raoult's Law10:27
- Distilling a Mixture of Two Liquids11:41
- Distilling a Mixture of Two Liquids11:42
- Simple Distillation: Changing Vapor Composition12:06
- Vapor & Liquid12:07
- Simple Distillation: Changing Vapor Composition14:47
- Azeotrope18:41
- Fractional Distillation: Constant Vapor Composition19:42
- Fractional Distillation: Constant Vapor Composition19:43
24m 13s
- Intro0:00
- Glassware Overview0:04
- Heating a Sample3:09
- Bunsen Burner3:10
- Heating Mantle 14:45
- Heating Mantle 26:18
- Hot Plate7:10
- Simple Distillation Lab8:37
- Fractional Distillation Lab17:13
- Removing the Distillation Set-Up22:41
28m 51s
- Intro0:00
- Chromatography0:06
- Purification & Analysis0:07
- Types of Chromatography: Thin-layer, Column, Gas, & High Performance Liquid0:24
- Theory of Chromatography0:44
- Theory of Chromatography0:45
- Performing a Thin-layer Chromatography (TLC) Analysis2:30
- Overview: Thin-layer Chromatography (TLC) Analysis2:31
- Step 1: 'Spot' the TLC Plate4:11
- Step 2: Prepare the Developing Chamber5:54
- Step 3: Develop the TLC Plate7:30
- Step 4: Visualize the Spots9:02
- Step 5: Calculate the Rf for Each Spot12:00
- Compound Polarity: Effect on Rf16:50
- Compound Polarity: Effect on Rf16:51
- Solvent Polarity: Effect on Rf18:47
- Solvent Polarity: Effect on Rf18:48
- Example: EtOAc & Hexane19:35
- Other Types of Chromatography22:27
- Thin-layer Chromatography (TLC)22:28
- Column Chromatography22:56
- High Performance Liquid (HPLC)23:59
- Gas Chromatography (GC)24:38
- Preparative 'prep' Scale Possible28:05
20m 50s
- Intro0:00
- Step 1: 'Spot' the TLC Plate0:06
- Step 2: Prepare the Developing Chamber4:06
- Step 3: Develop the TLC Plate6:26
- Step 4: Visualize the Spots7:45
- Step 5: Calculate the Rf for Each Spot11:48
- How to Make Spotters12:58
- TLC Plate16:04
- Flash Column Chromatography17:11
34m 25s
- Intro0:00
- Extraction Purify, Separate Mixtures0:07
- Adding a Second Solvent0:28
- Mixing Two Layers0:38
- Layers Settle0:54
- Separate Layers1:05
- Extraction Uses1:20
- To Separate Based on Difference in Solubility/Polarity1:21
- To Separate Based on Differences in Reactivity2:11
- Separate & Isolate2:20
- Theory of Extraction3:03
- Aqueous & Organic Phases3:04
- Solubility: 'Like Dissolves Like'3:25
- Separation of Layers4:06
- Partitioning4:14
- Distribution Coefficient, K5:03
- Solutes Partition Between Phases5:04
- Distribution Coefficient, K at Equilibrium6:27
- Acid-Base Extractions8:09
- Organic Layer8:10
- Adding Aqueous HCl & Mixing Two Layers8:46
- Neutralize (Adding Aqueous NaOH)10:05
- Adding Organic Solvent Mix Two Layers 'Back Extract'10:24
- Final Results10:43
- Planning an Acid-Base Extraction, Part 111:01
- Solute Type: Neutral11:02
- Aqueous Solution: Water13:40
- Solute Type: Basic14:43
- Solute Type: Weakly Acidic15:23
- Solute Type: Acidic16:12
- Planning an Acid-Base Extraction, Part 217:34
- Planning an Acid-Base Extraction17:35
- Performing an Extraction19:34
- Pour Solution into Sep Funnel19:35
- Add Second Liquid20:07
- Add Stopper, Cover with Hand, Remove from Ring20:48
- Tip Upside Down, Open Stopcock to Vent Pressure21:00
- Shake to Mix Two Layers21:30
- Remove Stopper & Drain Bottom Layer21:40
- Reaction Work-up: Purify, Isolate Product22:03
- Typical Reaction is Run in Organic Solvent22:04
- Starting a Reaction Work-up22:33
- Extracting the Product with Organic Solvent23:17
- Combined Extracts are Washed23:40
- Organic Layer is 'Dried'24:23
- Finding the Product26:38
- Which Layer is Which?26:39
- Where is My Product?28:00
- Tips, Tricks and Warnings29:29
- Leaking Sep Funnel29:30
- Caution When Mixing Layers & Using Ether30:17
- If an Emulsion Forms31:51
14m 49s
- Intro0:00
- Step 1: Preparing the Separatory Funnel0:03
- Step 2: Adding Sample1:18
- Step 3: Mixing the Two Layers2:59
- Step 4: Draining the Bottom Layers4:59
- Step 5: Performing a Second Extraction5:50
- Step 6: Drying the Organic Layer7:21
- Step 7: Gravity Filtration9:35
- Possible Extraction Challenges12:55
1h 4m
- Intro0:00
- Infrared (IR) Spectroscopy0:09
- Introduction to Infrared (IR) Spectroscopy0:10
- Intensity of Absorption Is Proportional to Change in Dipole3:08
- IR Spectrum of an Alkane6:08
- Pentane6:09
- IR Spectrum of an Alkene13:12
- 1-Pentene13:13
- IR Spectrum of an Alkyne15:49
- 1-Pentyne15:50
- IR Spectrum of an Aromatic Compound18:02
- Methylbenzene18:24
- IR of Substituted Aromatic Compounds24:04
- IR of Substituted Aromatic Compounds24:05
- IR Spectrum of 1,2-Disubstituted Aromatic25:30
- 1,2-dimethylbenzene25:31
- IR Spectrum of 1,3-Disubstituted Aromatic27:15
- 1,3-dimethylbenzene27:16
- IR Spectrum of 1,4-Disubstituted Aromatic28:41
- 1,4-dimethylbenzene28:42
- IR Spectrum of an Alcohol29:34
- 1-pentanol29:35
- IR Spectrum of an Amine32:39
- 1-butanamine32:40
- IR Spectrum of a 2° Amine34:50
- Diethylamine34:51
- IR Spectrum of a 3° Amine35:47
- Triethylamine35:48
- IR Spectrum of a Ketone36:41
- 2-butanone36:42
- IR Spectrum of an Aldehyde40:10
- Pentanal40:11
- IR Spectrum of an Ester42:38
- Butyl Propanoate42:39
- IR Spectrum of a Carboxylic Acid44:26
- Butanoic Acid44:27
- Sample IR Correlation Chart47:36
- Sample IR Correlation Chart: Wavenumber and Functional Group47:37
- Predicting IR Spectra: Sample Structures52:06
- Example 152:07
- Example 253:29
- Example 354:40
- Example 457:08
- Example 558:31
- Example 659:07
- Example 71:00:52
- Example 81:02:20
48m 34s
- Intro0:00
- Interpretation of IR Spectra: a Basic Approach0:05
- Interpretation of IR Spectra: a Basic Approach0:06
- Other Peaks to Look for3:39
- Examples5:17
- Example 15:18
- Example 29:09
- Example 311:52
- Example 414:03
- Example 516:31
- Example 619:31
- Example 722:32
- Example 824:39
- IR Problems Part 128:11
- IR Problem 128:12
- IR Problem 231:14
- IR Problem 332:59
- IR Problem 434:23
- IR Problem 535:49
- IR Problem 638:20
- IR Problems Part 242:36
- IR Problem 742:37
- IR Problem 844:02
- IR Problem 945:07
- IR Problems1046:10
1h 32m 14s
- Intro0:00
- Purpose of NMR0:14
- Purpose of NMR0:15
- How NMR Works2:17
- How NMR Works2:18
- Information Obtained From a ¹H NMR Spectrum5:51
- # of Signals, Integration, Chemical Shifts, and Splitting Patterns5:52
- Number of Signals in NMR (Chemical Equivalence)7:52
- Example 1: How Many Signals in ¹H NMR?7:53
- Example 2: How Many Signals in ¹H NMR?9:36
- Example 3: How Many Signals in ¹H NMR?12:15
- Example 4: How Many Signals in ¹H NMR?13:47
- Example 5: How Many Signals in ¹H NMR?16:12
- Size of Signals in NMR (Peak Area or Integration)21:23
- Size of Signals in NMR (Peak Area or Integration)21:24
- Using Integral Trails25:15
- Example 1: C₈H₁₈O25:16
- Example 2: C₃H₈O27:17
- Example 3: C₇H₈28:21
- Location of NMR Signal (Chemical Shift)29:05
- Location of NMR Signal (Chemical Shift)29:06
- ¹H NMR Chemical Shifts33:20
- ¹H NMR Chemical Shifts33:21
- ¹H NMR Chemical Shifts (Protons on Carbon)37:03
- ¹H NMR Chemical Shifts (Protons on Carbon)37:04
- Chemical Shifts of H's on N or O39:01
- Chemical Shifts of H's on N or O39:02
- Estimating Chemical Shifts41:13
- Example 1: Estimating Chemical Shifts41:14
- Example 2: Estimating Chemical Shifts43:22
- Functional Group Effects are Additive45:28
- Calculating Chemical Shifts47:38
- Methylene Calculation47:39
- Methine Calculation48:20
- Protons on sp³ Carbons: Chemical Shift Calculation Table48:50
- Example: Estimate the Chemical Shift of the Selected H50:29
- Effects of Resonance on Chemical Shifts53:11
- Example 1: Effects of Resonance on Chemical Shifts53:12
- Example 2: Effects of Resonance on Chemical Shifts55:09
- Example 3: Effects of Resonance on Chemical Shifts57:08
- Shape of NMR Signal (Splitting Patterns)59:17
- Shape of NMR Signal (Splitting Patterns)59:18
- Understanding Splitting Patterns: The 'n+1 Rule'1:01:24
- Understanding Splitting Patterns: The 'n+1 Rule'1:01:25
- Explanation of n+1 Rule1:02:42
- Explanation of n+1 Rule: One Neighbor1:02:43
- Explanation of n+1 Rule: Two Neighbors1:06:23
- Summary of Splitting Patterns1:06:24
- Summary of Splitting Patterns1:10:45
- Predicting ¹H NMR Spectra1:10:46
- Example 1: Predicting ¹H NMR Spectra1:13:30
- Example 2: Predicting ¹H NMR Spectra1:19:07
- Example 3: Predicting ¹H NMR Spectra1:23:50
- Example 4: Predicting ¹H NMR Spectra1:29:27
2h 3m 48s
- Intro0:00
- ¹H NMR Problem-Solving Strategies0:18
- Step 1: Analyze IR Spectrum (If Provided)0:19
- Step 2: Analyze Molecular Formula (If Provided)2:06
- Step 3: Draw Pieces of Molecule3:49
- Step 4: Confirm Piecs6:30
- Step 5: Put the Pieces Together!7:23
- Step 6: Check Your Answer!8:21
- Examples9:17
- Example 1: Determine the Structure of a C₉H₁₀O₂ Compound with the Following ¹H NMR Data9:18
- Example 2: Determine the Structure of a C₉H₁₀O₂ Compound with the Following ¹H NMR Data17:27
- ¹H NMR Practice20:57
- ¹H NMR Practice 1: C₁₀H₁₄20:58
- ¹H NMR Practice 2: C₄H₈O₂29:50
- ¹H NMR Practice 3: C₆H₁₂O₃39:19
- ¹H NMR Practice 4: C₈H₁₈50:19
- More About Coupling Constants (J Values)57:11
- Vicinal (3-bond) and Geminal (2-bond)57:12
- Cyclohexane (ax-ax) and Cyclohexane (ax-eq) or (eq-eq)59:50
- Geminal (Alkene), Cis (Alkene), and Trans (Alkene)1:02:40
- Allylic (4-bond) and W-coupling (4-bond) (Rigid Structures Only)1:04:05
- ¹H NMR Advanced Splitting Patterns1:05:39
- Example 1: ¹H NMR Advanced Splitting Patterns1:05:40
- Example 2: ¹H NMR Advanced Splitting Patterns1:10:01
- Example 3: ¹H NMR Advanced Splitting Patterns1:13:45
- ¹H NMR Practice1:22:53
- ¹H NMR Practice 5: C₁₁H₁₇N1:22:54
- ¹H NMR Practice 6: C₉H₁₀O1:34:04
- ¹³C NMR Spectroscopy1:44:49
- ¹³C NMR Spectroscopy1:44:50
- ¹³C NMR Chemical Shifts1:47:24
- ¹³C NMR Chemical Shifts Part 11:47:25
- ¹³C NMR Chemical Shifts Part 21:48:59
- ¹³C NMR Practice1:50:16
- ¹³C NMR Practice 11:50:17
- ¹³C NMR Practice 21:58:30
1h 28m 35s
- Intro0:00
- Introduction to Mass Spectrometry0:37
- Uses of Mass Spectrometry: Molecular Mass0:38
- Uses of Mass Spectrometry: Molecular Formula1:04
- Uses of Mass Spectrometry: Structural Information1:21
- Uses of Mass Spectrometry: In Conjunction with Gas Chromatography2:03
- Obtaining a Mass Spectrum2:59
- Obtaining a Mass Spectrum3:00
- The Components of a Mass Spectrum6:44
- The Components of a Mass Spectrum6:45
- What is the Mass of a Single Molecule12:13
- Example: CH₄12:14
- Example: ¹³CH₄12:51
- What Ratio is Expected for the Molecular Ion Peaks of C₂H₆?14:20
- Other Isotopes of High Abundance16:30
- Example: Cl Atoms16:31
- Example: Br Atoms18:33
- Mass Spectrometry of Chloroethane19:22
- Mass Spectrometry of Bromobutane21:23
- Isotopic Abundance can be Calculated22:48
- What Ratios are Expected for the Molecular Ion Peaks of CH₂Br₂?22:49
- Determining Molecular Formula from High-resolution Mass Spectrometry26:53
- Exact Masses of Various Elements26:54
- Fragmentation of various Functional Groups28:42
- What is More Stable, a Carbocation C⁺ or a Radical R?28:43
- Fragmentation is More Likely If It Gives Relatively Stable Carbocations and Radicals31:37
- Mass Spectra of Alkanes33:15
- Example: Hexane33:16
- Fragmentation Method 134:19
- Fragmentation Method 235:46
- Fragmentation Method 336:15
- Mass of Common Fragments37:07
- Mass of Common Fragments37:08
- Mass Spectra of Alkanes39:28
- Mass Spectra of Alkanes39:29
- What are the Peaks at m/z 15 and 71 So Small?41:01
- Branched Alkanes43:12
- Explain Why the Base Peak of 2-methylhexane is at m/z 43 (M-57)43:13
- Mass Spectra of Alkenes45:42
- Mass Spectra of Alkenes: Remove 1 e⁻45:43
- Mass Spectra of Alkenes: Fragment46:14
- High-Energy Pi Electron is Most Likely Removed47:59
- Mass Spectra of Aromatic Compounds49:01
- Mass Spectra of Aromatic Compounds49:02
- Mass Spectra of Alcohols51:32
- Mass Spectra of Alcohols51:33
- Mass Spectra of Ethers54:53
- Mass Spectra of Ethers54:54
- Mass Spectra of Amines56:49
- Mass Spectra of Amines56:50
- Mass Spectra of Aldehydes & Ketones59:23
- Mass Spectra of Aldehydes & Ketones59:24
- McLafferty Rearrangement1:01:29
- McLafferty Rearrangement1:01:30
- Mass Spectra of Esters1:04:15
- Mass Spectra of Esters1:01:16
- Mass Spectrometry Discussion I1:05:01
- For the Given Molecule (M=58), Do You Expect the More Abundant Peak to Be m/z 15 or m/z 43?1:05:02
- Mass Spectrometry Discussion II1:08:13
- For the Given Molecule (M=74), Do You Expect the More Abundant Peak to Be m/z 31, m/z 45, or m/z 59?1:08:14
- Mass Spectrometry Discussion III1:11:42
- Explain Why the Mass Spectra of Methyl Ketones Typically have a Peak at m/z 431:11:43
- Mass Spectrometry Discussion IV1:14:46
- In the Mass Spectrum of the Given Molecule (M=88), Account for the Peaks at m/z 45 and m/z 571:14:47
- Mass Spectrometry Discussion V1:18:25
- How Could You Use Mass Spectrometry to Distinguish Between the Following Two Compounds (M=73)?1:18:26
- Mass Spectrometry Discussion VI1:22:45
- What Would be the m/z Ratio for the Fragment for the Fragment Resulting from a McLafferty Rearrangement for the Following Molecule (M=114)?1:22:46
For more information, please see full course syllabus of Organic Chemistry Lab
Organic Chemistry Lab Mass Spectrometry
Mass Spectrometry gives the molecular weight of different components of a molecule. It can be used in conjunction with Gas Chromatography (GC-MS) to identify the molecular masses of components of a mixture. Gaseous molecules are ionized with a beam of electrons. The radical cation then breaks apart into charged and uncharged segments of different molecular weights, with the most stable being the most common (common fragmentation patterns can be identified, like the McLafferty Rearrangement for carbonyls). The particles are then passed through a magnetic field which separates them based on their mass-to-charge ratio (m/z). The biggest peak is called the “base peak” and set to a value of 100. Isotopes like Carbon-13 as well as Cl-35 and Cl-37 are important because the molecular masses are a weighted average of the isotopes. Examples in this lecture include chloroethane, bromobutane, hexane, ethers, alkenes, amines, and aromatic groups.
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1 answer
Last reply by: Professor Starkey
Thu Aug 4, 2016 4:37 PM
Post by Adel Althaqafy on August 3, 2016
Hi Dr
thank you for explain mass spectroscopy and do you have any articles that by PDF to read it or something is short like summarize about mass spectroscopy
many thanks
1 answer
Last reply by: Professor Starkey
Sun Oct 18, 2015 11:04 AM
Post by Jinhai Zhang on October 17, 2015
Prof. Starkey:
I have a question about the McLafferty mechanism should I use the double-headed arrow or single-headed arrow, because I google this, the web gives me a single headed arrow instead of double headed, and the mechanism is a little bit different from yours?
1 answer
Last reply by: Professor Starkey
Wed Sep 16, 2015 12:16 AM
Post by Tamrat Regasa on September 15, 2015
how can i sketch mass spectrum for 2 phenyl butane?
1 answer
Last reply by: Professor Starkey
Mon Jan 5, 2015 11:45 PM
Post by Rene Whitaker on January 5, 2015
I am still not understanding how you determine the M+ peak in chloroethane (at 20:52) and bromobutane, other than you know the compound you are looking at and so know at about what amu you should be looking at. For example, at 20:52, if you did not know the compound was chloroethane, how would you know the peak labeled at M+ is not the base peak (since it is at 100% relative abundance)?
1 answer
Last reply by: Professor Starkey
Sun Oct 26, 2014 12:53 AM
Post by Datevig Daghlian on October 24, 2014
Professor Starkey,
Thank you very much for your lectures! I am currently a high school student and have taken AP Chemistry and am very interested in O. Chemistry. Would you recommend I watch your lectures on O. Chemistry or should I hold off till I get to University Chemistry? Thank you!
George D.
3 answers
Last reply by: Professor Starkey
Thu Sep 11, 2014 10:07 AM
Post by Brandon West on September 9, 2014
Do you have a systematic way of doing mass spec like you have for HNMR and IR. I really like the systematic approach you have for HNMR. In my organic class my professor will give me all 3(HNMR or c13NMR, IR, and mass spec) and I will use all three to determine the structure.
1 answer
Last reply by: Professor Starkey
Thu Jul 17, 2014 4:17 PM
Post by Kim Tran on July 17, 2014
Professor Starkey, is there anyway I can open the lecture slides in powerpoint? Thank you
1 answer
Last reply by: Professor Starkey
Tue Mar 18, 2014 12:15 AM
Post by saima khwaja on March 17, 2014
Professor Starkey,
Do you do any lectures on Organometallic Compounds?
1 answer
Last reply by: Professor Starkey
Thu Feb 13, 2014 12:17 AM
Post by Jude Nawlo on February 12, 2014
Going back to the mass spectra of aromatic compounds section: If we see 91 amu on the MS, then do we assume that our compound has the "base" with the double bond on the CH2 or does it not matter, considering the benzylic resonance forms coexist? Awesome lecture, thank you again!
1 answer
Last reply by: Professor Starkey
Fri Jan 24, 2014 10:45 AM
Post by Udoka Ofoedu on January 24, 2014
You are the best . Thank God he brought me here
1 answer
Last reply by: Professor Starkey
Fri Oct 25, 2013 10:05 PM
Post by Saif Al-Wahaibi on October 25, 2013
For the McLafferty problem, where would the positive charge be in C4H8O so that it would be observed in the mass spectrometer?
1 answer
Last reply by: Professor Starkey
Wed Sep 11, 2013 11:05 AM
Post by Ramin Sadat on September 10, 2013
Thank you for the Mass Spectrometry lecture. I have been waiting for this! Very Helpful!