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Lecture Comments (26)

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!

Mass Spectrometry

Lecture Slides are screen-captured images of important points in the lecture. Students can download and print out these lecture slide images to do practice problems as well as take notes while watching the lecture.

  1. Intro
    • Introduction to Mass Spectrometry
    • Obtaining a Mass Spectrum
    • The Components of a Mass Spectrum
    • What is the Mass of a Single Molecule
    • Other Isotopes of High Abundance
    • Isotopic Abundance can be Calculated
    • Determining Molecular Formula from High-resolution Mass Spectrometry
    • Fragmentation of various Functional Groups
    • Mass Spectra of Alkanes
    • Mass of Common Fragments
    • Mass Spectra of Alkanes
    • Branched Alkanes
    • Mass Spectra of Alkenes
    • Mass Spectra of Aromatic Compounds
    • Mass Spectra of Alcohols
    • Mass Spectra of Ethers
    • Mass Spectra of Amines
    • Mass Spectra of Aldehydes & Ketones
    • McLafferty Rearrangement
    • Mass Spectra of Esters
    • Mass Spectrometry Discussion I
    • Mass Spectrometry Discussion II
    • Mass Spectrometry Discussion III
    • Mass Spectrometry Discussion IV
    • Mass Spectrometry Discussion V
    • Mass Spectrometry Discussion VI
    • Intro 0:00
    • Introduction to Mass Spectrometry 0:37
      • Uses of Mass Spectrometry: Molecular Mass
      • Uses of Mass Spectrometry: Molecular Formula
      • Uses of Mass Spectrometry: Structural Information
      • Uses of Mass Spectrometry: In Conjunction with Gas Chromatography
    • Obtaining a Mass Spectrum 2:59
      • Obtaining a Mass Spectrum
    • The Components of a Mass Spectrum 6:44
      • The Components of a Mass Spectrum
    • What is the Mass of a Single Molecule 12:13
      • Example: CH₄
      • Example: ¹³CH₄
      • What Ratio is Expected for the Molecular Ion Peaks of C₂H₆?
    • Other Isotopes of High Abundance 16:30
      • Example: Cl Atoms
      • Example: Br Atoms
      • Mass Spectrometry of Chloroethane
      • Mass Spectrometry of Bromobutane
    • Isotopic Abundance can be Calculated 22:48
      • What Ratios are Expected for the Molecular Ion Peaks of CH₂Br₂?
    • Determining Molecular Formula from High-resolution Mass Spectrometry 26:53
      • Exact Masses of Various Elements
    • Fragmentation of various Functional Groups 28:42
      • What is More Stable, a Carbocation C⁺ or a Radical R?
      • Fragmentation is More Likely If It Gives Relatively Stable Carbocations and Radicals
    • Mass Spectra of Alkanes 33:15
      • Example: Hexane
      • Fragmentation Method 1
      • Fragmentation Method 2
      • Fragmentation Method 3
    • Mass of Common Fragments 37:07
      • Mass of Common Fragments
    • Mass Spectra of Alkanes 39:28
      • Mass Spectra of Alkanes
      • What are the Peaks at m/z 15 and 71 So Small?
    • Branched Alkanes 43:12
      • Explain Why the Base Peak of 2-methylhexane is at m/z 43 (M-57)
    • Mass Spectra of Alkenes 45:42
      • Mass Spectra of Alkenes: Remove 1 e⁻
      • Mass Spectra of Alkenes: Fragment
      • High-Energy Pi Electron is Most Likely Removed
    • Mass Spectra of Aromatic Compounds 49:01
      • Mass Spectra of Aromatic Compounds
    • Mass Spectra of Alcohols 51:32
      • Mass Spectra of Alcohols
    • Mass Spectra of Ethers 54:53
      • Mass Spectra of Ethers
    • Mass Spectra of Amines 56:49
      • Mass Spectra of Amines
    • Mass Spectra of Aldehydes & Ketones 59:23
      • Mass Spectra of Aldehydes & Ketones
    • McLafferty Rearrangement 1:01:29
      • McLafferty Rearrangement
    • Mass Spectra of Esters 1:04:15
      • Mass Spectra of Esters
    • Mass Spectrometry Discussion I 1:05:01
      • For the Given Molecule (M=58), Do You Expect the More Abundant Peak to Be m/z 15 or m/z 43?
    • Mass Spectrometry Discussion II 1:08:13
      • 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?
    • Mass Spectrometry Discussion III 1:11:42
      • Explain Why the Mass Spectra of Methyl Ketones Typically have a Peak at m/z 43
    • Mass Spectrometry Discussion IV 1:14:46
      • In the Mass Spectrum of the Given Molecule (M=88), Account for the Peaks at m/z 45 and m/z 57
    • Mass Spectrometry Discussion V 1:18:25
      • How Could You Use Mass Spectrometry to Distinguish Between the Following Two Compounds (M=73)?
    • Mass Spectrometry Discussion VI 1:22:45
      • What Would be the m/z Ratio for the Fragment for the Fragment Resulting from a McLafferty Rearrangement for the Following Molecule (M=114)?
    Dr. Laurie Starkey

    Dr. Laurie Starkey

    Mass Spectrometry

    Slide Duration:

    Table of Contents

    Section 1: Reagent Table
    Completing the Reagent Table for Prelab

    21m 9s

    Intro
    0:00
    Sample Reagent Table
    0:11
    Reagent Table Overview
    0:12
    Calculate Moles of 2-bromoaniline
    6:44
    Calculate Molar Amounts of Each Reagent
    9:20
    Calculate Mole of NaNO₂
    9:21
    Calculate Moles of KI
    10:33
    Identify the Limiting Reagent
    11:17
    Which Reagent is the Limiting Reagent?
    11:18
    Calculate Molar Equivalents
    13:37
    Molar Equivalents
    13:38
    Calculate Theoretical Yield
    16:40
    Theoretical Yield
    16:41
    Calculate Actual Yield (%Yield)
    18:30
    Actual Yield (%Yield)
    18:31
    Section 2: Melting Points
    Introduction to Melting Points

    16m 10s

    Intro
    0:00
    Definition of a Melting Point (mp)
    0:04
    Definition of a Melting Point (mp)
    0:05
    Solid Samples Melt Gradually
    1:49
    Recording Range of Melting Temperature
    2:04
    Melting Point Theory
    3:14
    Melting Point Theory
    3:15
    Effects of Impurities on a Melting Point
    3:57
    Effects of Impurities on a Melting Point
    3:58
    Special Exception: Eutectic Mixtures
    5:09
    Freezing Point Depression by Solutes
    5:39
    Melting Point Uses
    6:19
    Solid Compound
    6:20
    Determine Purity of a Sample
    6:42
    Identify an Unknown Solid
    7:06
    Recording a Melting Point
    9:03
    Pack 1-3 mm of Dry Powder in MP Tube
    9:04
    Slowly Heat Sample
    9:55
    Record Temperature at First Sign of Melting
    10:33
    Record Temperature When Last Crystal Disappears
    11:26
    Discard MP Tube in Glass Waste
    11:32
    Determine Approximate MP
    11:42
    Tips, Tricks and Warnings
    12:28
    Use Small, Tightly Packed Sample
    12:29
    Be Sure MP Apparatus is Cool
    12:45
    Never Reuse a MP Tube
    13:16
    Sample May Decompose
    13:30
    If Pure Melting Point (MP) Doesn't Match Literature
    14:20
    Melting Point Lab

    8m 17s

    Intro
    0:00
    Melting Point Tubes
    0:40
    Melting Point Apparatus
    3:42
    Recording a melting Point
    5:50
    Section 3: Recrystallization
    Introduction to Recrystallization

    22m

    Intro
    0:00
    Crystallization to Purify a Solid
    0:10
    Crude Solid
    0:11
    Hot Solution
    0:20
    Crystals
    1:09
    Supernatant Liquid
    1:20
    Theory of Crystallization
    2:34
    Theory of Crystallization
    2:35
    Analysis and Obtaining a Second Crop
    3:40
    Crystals → Melting Point, TLC
    3:41
    Supernatant Liquid → Crude Solid → Pure Solid
    4:18
    Crystallize Again → Pure Solid (2nd Crop)
    4:32
    Choosing a Solvent
    5:19
    1. Product is Very Soluble at High Temperatures
    5:20
    2. Product has Low Solubility at Low Temperatures
    6:00
    3. Impurities are Soluble at All Temperatures
    6:16
    Check Handbooks for Suitable Solvents
    7:33
    Why Isn't This Dissolving?!
    8:46
    If Solid Remains When Solution is Hot
    8:47
    Still Not Dissolved in Hot Solvent?
    10:18
    Where Are My Crystals?!
    12:23
    If No Crystals Form When Solution is Cooled
    12:24
    Still No Crystals?
    14:59
    Tips, Tricks and Warnings
    16:26
    Always Use a Boiling Chip or Stick!
    16:27
    Use Charcoal to Remove Colored Impurities
    16:52
    Solvent Pairs May Be Used
    18:23
    Product May 'Oil Out'
    20:11
    Recrystallization Lab

    19m 7s

    Intro
    0:00
    Step 1: Dissolving the Solute in the Solvent
    0:12
    Hot Filtration
    6:33
    Step 2: Cooling the Solution
    8:01
    Step 3: Filtering the Crystals
    12:08
    Step 4: Removing & Drying the Crystals
    16:10
    Section 4: Distillation
    Introduction to Distillation

    25m 54s

    Intro
    0:00
    Distillation: Purify a Liquid
    0:04
    Simple Distillation
    0:05
    Fractional Distillation
    0:55
    Theory of Distillation
    1:04
    Theory of Distillation
    1:05
    Vapor Pressure and Volatility
    1:52
    Vapor Pressure
    1:53
    Volatile Liquid
    2:28
    Less Volatile Liquid
    3:09
    Vapor Pressure vs. Boiling Point
    4:03
    Vapor Pressure vs. Boiling Point
    4:04
    Increasing Vapor Pressure
    4:38
    The Purpose of Boiling Chips
    6:46
    The Purpose of Boiling Chips
    6:47
    Homogeneous Mixtures of Liquids
    9:24
    Dalton's Law
    9:25
    Raoult's Law
    10:27
    Distilling a Mixture of Two Liquids
    11:41
    Distilling a Mixture of Two Liquids
    11:42
    Simple Distillation: Changing Vapor Composition
    12:06
    Vapor & Liquid
    12:07
    Simple Distillation: Changing Vapor Composition
    14:47
    Azeotrope
    18:41
    Fractional Distillation: Constant Vapor Composition
    19:42
    Fractional Distillation: Constant Vapor Composition
    19:43
    Distillation Lab

    24m 13s

    Intro
    0:00
    Glassware Overview
    0:04
    Heating a Sample
    3:09
    Bunsen Burner
    3:10
    Heating Mantle 1
    4:45
    Heating Mantle 2
    6:18
    Hot Plate
    7:10
    Simple Distillation Lab
    8:37
    Fractional Distillation Lab
    17:13
    Removing the Distillation Set-Up
    22:41
    Section 5: Chromatography
    Introduction to TLC (Thin-Layer Chromatography)

    28m 51s

    Intro
    0:00
    Chromatography
    0:06
    Purification & Analysis
    0:07
    Types of Chromatography: Thin-layer, Column, Gas, & High Performance Liquid
    0:24
    Theory of Chromatography
    0:44
    Theory of Chromatography
    0:45
    Performing a Thin-layer Chromatography (TLC) Analysis
    2:30
    Overview: Thin-layer Chromatography (TLC) Analysis
    2:31
    Step 1: 'Spot' the TLC Plate
    4:11
    Step 2: Prepare the Developing Chamber
    5:54
    Step 3: Develop the TLC Plate
    7:30
    Step 4: Visualize the Spots
    9:02
    Step 5: Calculate the Rf for Each Spot
    12:00
    Compound Polarity: Effect on Rf
    16:50
    Compound Polarity: Effect on Rf
    16:51
    Solvent Polarity: Effect on Rf
    18:47
    Solvent Polarity: Effect on Rf
    18:48
    Example: EtOAc & Hexane
    19:35
    Other Types of Chromatography
    22:27
    Thin-layer Chromatography (TLC)
    22:28
    Column Chromatography
    22:56
    High Performance Liquid (HPLC)
    23:59
    Gas Chromatography (GC)
    24:38
    Preparative 'prep' Scale Possible
    28:05
    TLC Analysis Lab

    20m 50s

    Intro
    0:00
    Step 1: 'Spot' the TLC Plate
    0:06
    Step 2: Prepare the Developing Chamber
    4:06
    Step 3: Develop the TLC Plate
    6:26
    Step 4: Visualize the Spots
    7:45
    Step 5: Calculate the Rf for Each Spot
    11:48
    How to Make Spotters
    12:58
    TLC Plate
    16:04
    Flash Column Chromatography
    17:11
    Section 6: Extractions
    Introduction to Extractions

    34m 25s

    Intro
    0:00
    Extraction Purify, Separate Mixtures
    0:07
    Adding a Second Solvent
    0:28
    Mixing Two Layers
    0:38
    Layers Settle
    0:54
    Separate Layers
    1:05
    Extraction Uses
    1:20
    To Separate Based on Difference in Solubility/Polarity
    1:21
    To Separate Based on Differences in Reactivity
    2:11
    Separate & Isolate
    2:20
    Theory of Extraction
    3:03
    Aqueous & Organic Phases
    3:04
    Solubility: 'Like Dissolves Like'
    3:25
    Separation of Layers
    4:06
    Partitioning
    4:14
    Distribution Coefficient, K
    5:03
    Solutes Partition Between Phases
    5:04
    Distribution Coefficient, K at Equilibrium
    6:27
    Acid-Base Extractions
    8:09
    Organic Layer
    8:10
    Adding Aqueous HCl & Mixing Two Layers
    8:46
    Neutralize (Adding Aqueous NaOH)
    10:05
    Adding Organic Solvent Mix Two Layers 'Back Extract'
    10:24
    Final Results
    10:43
    Planning an Acid-Base Extraction, Part 1
    11:01
    Solute Type: Neutral
    11:02
    Aqueous Solution: Water
    13:40
    Solute Type: Basic
    14:43
    Solute Type: Weakly Acidic
    15:23
    Solute Type: Acidic
    16:12
    Planning an Acid-Base Extraction, Part 2
    17:34
    Planning an Acid-Base Extraction
    17:35
    Performing an Extraction
    19:34
    Pour Solution into Sep Funnel
    19:35
    Add Second Liquid
    20:07
    Add Stopper, Cover with Hand, Remove from Ring
    20:48
    Tip Upside Down, Open Stopcock to Vent Pressure
    21:00
    Shake to Mix Two Layers
    21:30
    Remove Stopper & Drain Bottom Layer
    21:40
    Reaction Work-up: Purify, Isolate Product
    22:03
    Typical Reaction is Run in Organic Solvent
    22:04
    Starting a Reaction Work-up
    22:33
    Extracting the Product with Organic Solvent
    23:17
    Combined Extracts are Washed
    23:40
    Organic Layer is 'Dried'
    24:23
    Finding the Product
    26:38
    Which Layer is Which?
    26:39
    Where is My Product?
    28:00
    Tips, Tricks and Warnings
    29:29
    Leaking Sep Funnel
    29:30
    Caution When Mixing Layers & Using Ether
    30:17
    If an Emulsion Forms
    31:51
    Extraction Lab

    14m 49s

    Intro
    0:00
    Step 1: Preparing the Separatory Funnel
    0:03
    Step 2: Adding Sample
    1:18
    Step 3: Mixing the Two Layers
    2:59
    Step 4: Draining the Bottom Layers
    4:59
    Step 5: Performing a Second Extraction
    5:50
    Step 6: Drying the Organic Layer
    7:21
    Step 7: Gravity Filtration
    9:35
    Possible Extraction Challenges
    12:55
    Section 7: Spectroscopy
    Infrared Spectroscopy, Part I

    1h 4m

    Intro
    0:00
    Infrared (IR) Spectroscopy
    0:09
    Introduction to Infrared (IR) Spectroscopy
    0:10
    Intensity of Absorption Is Proportional to Change in Dipole
    3:08
    IR Spectrum of an Alkane
    6:08
    Pentane
    6:09
    IR Spectrum of an Alkene
    13:12
    1-Pentene
    13:13
    IR Spectrum of an Alkyne
    15:49
    1-Pentyne
    15:50
    IR Spectrum of an Aromatic Compound
    18:02
    Methylbenzene
    18:24
    IR of Substituted Aromatic Compounds
    24:04
    IR of Substituted Aromatic Compounds
    24:05
    IR Spectrum of 1,2-Disubstituted Aromatic
    25:30
    1,2-dimethylbenzene
    25:31
    IR Spectrum of 1,3-Disubstituted Aromatic
    27:15
    1,3-dimethylbenzene
    27:16
    IR Spectrum of 1,4-Disubstituted Aromatic
    28:41
    1,4-dimethylbenzene
    28:42
    IR Spectrum of an Alcohol
    29:34
    1-pentanol
    29:35
    IR Spectrum of an Amine
    32:39
    1-butanamine
    32:40
    IR Spectrum of a 2° Amine
    34:50
    Diethylamine
    34:51
    IR Spectrum of a 3° Amine
    35:47
    Triethylamine
    35:48
    IR Spectrum of a Ketone
    36:41
    2-butanone
    36:42
    IR Spectrum of an Aldehyde
    40:10
    Pentanal
    40:11
    IR Spectrum of an Ester
    42:38
    Butyl Propanoate
    42:39
    IR Spectrum of a Carboxylic Acid
    44:26
    Butanoic Acid
    44:27
    Sample IR Correlation Chart
    47:36
    Sample IR Correlation Chart: Wavenumber and Functional Group
    47:37
    Predicting IR Spectra: Sample Structures
    52:06
    Example 1
    52:07
    Example 2
    53:29
    Example 3
    54:40
    Example 4
    57:08
    Example 5
    58:31
    Example 6
    59:07
    Example 7
    1:00:52
    Example 8
    1:02:20
    Infrared Spectroscopy, Part II

    48m 34s

    Intro
    0:00
    Interpretation of IR Spectra: a Basic Approach
    0:05
    Interpretation of IR Spectra: a Basic Approach
    0:06
    Other Peaks to Look for
    3:39
    Examples
    5:17
    Example 1
    5:18
    Example 2
    9:09
    Example 3
    11:52
    Example 4
    14:03
    Example 5
    16:31
    Example 6
    19:31
    Example 7
    22:32
    Example 8
    24:39
    IR Problems Part 1
    28:11
    IR Problem 1
    28:12
    IR Problem 2
    31:14
    IR Problem 3
    32:59
    IR Problem 4
    34:23
    IR Problem 5
    35:49
    IR Problem 6
    38:20
    IR Problems Part 2
    42:36
    IR Problem 7
    42:37
    IR Problem 8
    44:02
    IR Problem 9
    45:07
    IR Problems10
    46:10
    Nuclear Magnetic Resonance (NMR) Spectroscopy, Part I

    1h 32m 14s

    Intro
    0:00
    Purpose of NMR
    0:14
    Purpose of NMR
    0:15
    How NMR Works
    2:17
    How NMR Works
    2:18
    Information Obtained From a ¹H NMR Spectrum
    5:51
    # of Signals, Integration, Chemical Shifts, and Splitting Patterns
    5:52
    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 Trails
    25:15
    Example 1: C₈H₁₈O
    25:16
    Example 2: C₃H₈O
    27:17
    Example 3: C₇H₈
    28:21
    Location of NMR Signal (Chemical Shift)
    29:05
    Location of NMR Signal (Chemical Shift)
    29:06
    ¹H NMR Chemical Shifts
    33:20
    ¹H NMR Chemical Shifts
    33:21
    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 O
    39:01
    Chemical Shifts of H's on N or O
    39:02
    Estimating Chemical Shifts
    41:13
    Example 1: Estimating Chemical Shifts
    41:14
    Example 2: Estimating Chemical Shifts
    43:22
    Functional Group Effects are Additive
    45:28
    Calculating Chemical Shifts
    47:38
    Methylene Calculation
    47:39
    Methine Calculation
    48:20
    Protons on sp³ Carbons: Chemical Shift Calculation Table
    48:50
    Example: Estimate the Chemical Shift of the Selected H
    50:29
    Effects of Resonance on Chemical Shifts
    53:11
    Example 1: Effects of Resonance on Chemical Shifts
    53:12
    Example 2: Effects of Resonance on Chemical Shifts
    55:09
    Example 3: Effects of Resonance on Chemical Shifts
    57:08
    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 Rule
    1:02:42
    Explanation of n+1 Rule: One Neighbor
    1:02:43
    Explanation of n+1 Rule: Two Neighbors
    1:06:23
    Summary of Splitting Patterns
    1:06:24
    Summary of Splitting Patterns
    1:10:45
    Predicting ¹H NMR Spectra
    1:10:46
    Example 1: Predicting ¹H NMR Spectra
    1:13:30
    Example 2: Predicting ¹H NMR Spectra
    1:19:07
    Example 3: Predicting ¹H NMR Spectra
    1:23:50
    Example 4: Predicting ¹H NMR Spectra
    1:29:27
    Nuclear Magnetic Resonance (NMR) Spectroscopy, Part II

    2h 3m 48s

    Intro
    0:00
    ¹H NMR Problem-Solving Strategies
    0:18
    Step 1: Analyze IR Spectrum (If Provided)
    0:19
    Step 2: Analyze Molecular Formula (If Provided)
    2:06
    Step 3: Draw Pieces of Molecule
    3:49
    Step 4: Confirm Piecs
    6:30
    Step 5: Put the Pieces Together!
    7:23
    Step 6: Check Your Answer!
    8:21
    Examples
    9:17
    Example 1: Determine the Structure of a C₉H₁₀O₂ Compound with the Following ¹H NMR Data
    9:18
    Example 2: Determine the Structure of a C₉H₁₀O₂ Compound with the Following ¹H NMR Data
    17:27
    ¹H NMR Practice
    20:57
    ¹H NMR Practice 1: C₁₀H₁₄
    20:58
    ¹H NMR Practice 2: C₄H₈O₂
    29:50
    ¹H NMR Practice 3: C₆H₁₂O₃
    39:19
    ¹H NMR Practice 4: C₈H₁₈
    50:19
    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 Patterns
    1:05:39
    Example 1: ¹H NMR Advanced Splitting Patterns
    1:05:40
    Example 2: ¹H NMR Advanced Splitting Patterns
    1:10:01
    Example 3: ¹H NMR Advanced Splitting Patterns
    1:13:45
    ¹H NMR Practice
    1:22:53
    ¹H NMR Practice 5: C₁₁H₁₇N
    1:22:54
    ¹H NMR Practice 6: C₉H₁₀O
    1:34:04
    ¹³C NMR Spectroscopy
    1:44:49
    ¹³C NMR Spectroscopy
    1:44:50
    ¹³C NMR Chemical Shifts
    1:47:24
    ¹³C NMR Chemical Shifts Part 1
    1:47:25
    ¹³C NMR Chemical Shifts Part 2
    1:48:59
    ¹³C NMR Practice
    1:50:16
    ¹³C NMR Practice 1
    1:50:17
    ¹³C NMR Practice 2
    1:58:30
    Mass Spectrometry

    1h 28m 35s

    Intro
    0:00
    Introduction to Mass Spectrometry
    0:37
    Uses of Mass Spectrometry: Molecular Mass
    0:38
    Uses of Mass Spectrometry: Molecular Formula
    1:04
    Uses of Mass Spectrometry: Structural Information
    1:21
    Uses of Mass Spectrometry: In Conjunction with Gas Chromatography
    2:03
    Obtaining a Mass Spectrum
    2:59
    Obtaining a Mass Spectrum
    3:00
    The Components of a Mass Spectrum
    6:44
    The Components of a Mass Spectrum
    6:45
    What is the Mass of a Single Molecule
    12:13
    Example: CH₄
    12:14
    Example: ¹³CH₄
    12:51
    What Ratio is Expected for the Molecular Ion Peaks of C₂H₆?
    14:20
    Other Isotopes of High Abundance
    16:30
    Example: Cl Atoms
    16:31
    Example: Br Atoms
    18:33
    Mass Spectrometry of Chloroethane
    19:22
    Mass Spectrometry of Bromobutane
    21:23
    Isotopic Abundance can be Calculated
    22:48
    What Ratios are Expected for the Molecular Ion Peaks of CH₂Br₂?
    22:49
    Determining Molecular Formula from High-resolution Mass Spectrometry
    26:53
    Exact Masses of Various Elements
    26:54
    Fragmentation of various Functional Groups
    28:42
    What is More Stable, a Carbocation C⁺ or a Radical R?
    28:43
    Fragmentation is More Likely If It Gives Relatively Stable Carbocations and Radicals
    31:37
    Mass Spectra of Alkanes
    33:15
    Example: Hexane
    33:16
    Fragmentation Method 1
    34:19
    Fragmentation Method 2
    35:46
    Fragmentation Method 3
    36:15
    Mass of Common Fragments
    37:07
    Mass of Common Fragments
    37:08
    Mass Spectra of Alkanes
    39:28
    Mass Spectra of Alkanes
    39:29
    What are the Peaks at m/z 15 and 71 So Small?
    41:01
    Branched Alkanes
    43:12
    Explain Why the Base Peak of 2-methylhexane is at m/z 43 (M-57)
    43:13
    Mass Spectra of Alkenes
    45:42
    Mass Spectra of Alkenes: Remove 1 e⁻
    45:43
    Mass Spectra of Alkenes: Fragment
    46:14
    High-Energy Pi Electron is Most Likely Removed
    47:59
    Mass Spectra of Aromatic Compounds
    49:01
    Mass Spectra of Aromatic Compounds
    49:02
    Mass Spectra of Alcohols
    51:32
    Mass Spectra of Alcohols
    51:33
    Mass Spectra of Ethers
    54:53
    Mass Spectra of Ethers
    54:54
    Mass Spectra of Amines
    56:49
    Mass Spectra of Amines
    56:50
    Mass Spectra of Aldehydes & Ketones
    59:23
    Mass Spectra of Aldehydes & Ketones
    59:24
    McLafferty Rearrangement
    1:01:29
    McLafferty Rearrangement
    1:01:30
    Mass Spectra of Esters
    1:04:15
    Mass Spectra of Esters
    1:01:16
    Mass Spectrometry Discussion I
    1:05:01
    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 II
    1:08:13
    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 III
    1:11:42
    Explain Why the Mass Spectra of Methyl Ketones Typically have a Peak at m/z 43
    1:11:43
    Mass Spectrometry Discussion IV
    1:14:46
    In the Mass Spectrum of the Given Molecule (M=88), Account for the Peaks at m/z 45 and m/z 57
    1:14:47
    Mass Spectrometry Discussion V
    1:18:25
    How Could You Use Mass Spectrometry to Distinguish Between the Following Two Compounds (M=73)?
    1:18:26
    Mass Spectrometry Discussion VI
    1:22:45
    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
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