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Dr. Laurie Starkey brings her expertise in Organic Chemistry to help students learn important laboratory theory and techniques. She covers everything from melting point, distillation, and extraction, to more advanced concepts in chromatography and spectroscopy. Each lesson contains all the necessary steps to correctly assemble the apparatus and complete the experiment, followed by a comprehensive pre-lab discussion of theory, procedures, and calculations. This course is crucial for students who wish to excel in Organic Chemistry Laboratory in order to satisfy their degree or pre-medical requirements. Dr. Laurie Starkey is the author of “Introduction to Strategies for Organic Synthesis” (Wiley) and earned her Ph.D. in Chemistry from UCLA. She has been teaching Organic Chemistry at the university level for over 20 years and most recently won the 2013 Provost's Award for Excellence in Teaching, Cal Poly Pomona's highest teaching award.

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I. Reagent Table

  Completing the Reagent Table for Prelab 21:09
   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 

II. Melting Points

  Introduction to Melting Points 16:10
   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 8:17
   Intro 0:00 
   Melting Point Tubes 0:40 
   Melting Point Apparatus 3:42 
   Recording a melting Point 5:50 

III. Recrystallization

  Introduction to Recrystallization 22:00
   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 19:07
   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 

IV. Distillation

  Introduction to Distillation 25:54
   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 24:13
   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 

V. Chromatography

  Introduction to TLC (Thin-Layer Chromatography) 28:51
   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 20:50
   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 

VI. Extractions

  Introduction to Extractions 34:25
   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 14:49
   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 

VII. Spectroscopy

  Infrared Spectroscopy, Part I 1:04:00
   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 18:2 
    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 60:52 
    Example 8 62:20 
  Infrared Spectroscopy, Part II 48:34
   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 1:32:14
   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' 61:24 
    Understanding Splitting Patterns: The 'n+1 Rule' 61:25 
   Explanation of n+1 Rule 62:42 
    Explanation of n+1 Rule: One Neighbor 62:43 
    Explanation of n+1 Rule: Two Neighbors 66:23 
   Summary of Splitting Patterns 66:24 
    Summary of Splitting Patterns 70:45 
   Predicting ¹H NMR Spectra 70:46 
    Example 1: Predicting ¹H NMR Spectra 73:30 
    Example 2: Predicting ¹H NMR Spectra 79:07 
    Example 3: Predicting ¹H NMR Spectra 83:50 
    Example 4: Predicting ¹H NMR Spectra 89:27 
  Nuclear Magnetic Resonance (NMR) Spectroscopy, Part II 2:03:48
   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) 62:40 
    Allylic (4-bond) and W-coupling (4-bond) (Rigid Structures Only) 64:05 
   ¹H NMR Advanced Splitting Patterns 65:39 
    Example 1: ¹H NMR Advanced Splitting Patterns 65:40 
    Example 2: ¹H NMR Advanced Splitting Patterns 70:01 
    Example 3: ¹H NMR Advanced Splitting Patterns 73:45 
   ¹H NMR Practice 82:53 
    ¹H NMR Practice 5: C₁₁H₁₇N 82:54 
    ¹H NMR Practice 6: C₉H₁₀O 94:04 
   ¹³C NMR Spectroscopy 104:49 
    ¹³C NMR Spectroscopy 104:50 
   ¹³C NMR Chemical Shifts 107:24 
    ¹³C NMR Chemical Shifts Part 1 107:25 
    ¹³C NMR Chemical Shifts Part 2 108:59 
   ¹³C NMR Practice 110:16 
    ¹³C NMR Practice 1 110:17 
    ¹³C NMR Practice 2 118:30 
  Mass Spectrometry 1:28:35
   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 61:29 
    McLafferty Rearrangement 61:30 
   Mass Spectra of Esters 64:15 
    Mass Spectra of Esters 61:16 
   Mass Spectrometry Discussion I 65:01 
    For the Given Molecule (M=58), Do You Expect the More Abundant Peak to Be m/z 15 or m/z 43? 65:02 
   Mass Spectrometry Discussion II 68:13 
    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? 68:14 
   Mass Spectrometry Discussion III 71:42 
    Explain Why the Mass Spectra of Methyl Ketones Typically have a Peak at m/z 43 71:43 
   Mass Spectrometry Discussion IV 74:46 
    In the Mass Spectrum of the Given Molecule (M=88), Account for the Peaks at m/z 45 and m/z 57 74:47 
   Mass Spectrometry Discussion V 78:25 
    How Could You Use Mass Spectrometry to Distinguish Between the Following Two Compounds (M=73)? 78:26 
   Mass Spectrometry Discussion VI 82:45 
    What Would be the m/z Ratio for the Fragment for the Fragment Resulting from a McLafferty Rearrangement for the Following Molecule (M=114)? 82:46