Ch. 15 - Analytical Techniques: IR, NMR, Mass SpectWorksheetSee all chapters
All Chapters
Ch. 1 - A Review of General Chemistry
Ch. 2 - Molecular Representations
Ch. 3 - Acids and Bases
Ch. 4 - Alkanes and Cycloalkanes
Ch. 5 - Chirality
Ch. 6 - Thermodynamics and Kinetics
Ch. 7 - Substitution Reactions
Ch. 8 - Elimination Reactions
Ch. 9 - Alkenes and Alkynes
Ch. 10 - Addition Reactions
Ch. 11 - Radical Reactions
Ch. 12 - Alcohols, Ethers, Epoxides and Thiols
Ch. 13 - Alcohols and Carbonyl Compounds
Ch. 14 - Synthetic Techniques
Ch. 15 - Analytical Techniques: IR, NMR, Mass Spect
Ch. 16 - Conjugated Systems
Ch. 17 - Aromaticity
Ch. 18 - Reactions of Aromatics: EAS and Beyond
Ch. 19 - Aldehydes and Ketones: Nucleophilic Addition
Ch. 20 - Carboxylic Acid Derivatives: NAS
Ch. 21 - Enolate Chemistry: Reactions at the Alpha-Carbon
Ch. 22 - Condensation Chemistry
Ch. 23 - Amines
Ch. 24 - Carbohydrates
Ch. 25 - Phenols
Ch. 26 - Amino Acids, Peptides, and Proteins

Concept #1: 13C NMR General Features

Example #1: Identifying 13C Signals

Example #2: 1H and 13C Joint Problem

Additional Problems
How many signals would be observed in the proton-decoupled  13C NMR spectrum of the compound shown below? A) 5 B) 6 C) 7 D) 8
The chemical shifts in the 13C NMR spectrum for this compound are δ 15.8, 40.1, 51.8, and 170.2. Which is the correct set of chemical shifts for the carbon atoms?
Which isn’t true about 13C NMR spectroscopy?   a) Each distinct carbon produces a single peak in 13C NMR spectrum. b) Splitting of signals into multiple peaks is not observed in routine 13C NMR spectra. c) Decreased electron density around an atom shields the atom from the magnetic field. d) Larger mass of samples is usually required. e) 13C spectra are usually less complex and easier to interpret than 1H NMR.
How many peaks (signals) would you expect in the broadband- decoupled  13C NMR spectrum of each of the following compounds? Example: You should see 4 peaks (singles) in 2-butanone, CH 3COCH2CH3.  
In 13C NMR spectroscopy, the signal due to this type of carbon occurs furthest downfield.
For the following compound how many different signals would you see in the carbon NMR? (Assume that you can see them all.) A) 1 B) 2 C) 3 D) 4 E) 5
For the following compound how many different signals would you see in the carbon NMR? (Assume that you can see them all.) A) 4 B) 5 C) 6 D) 7 E) 8
How many signals would you expect to find in each range of the 13C-NMR spectrum of the following compounds? Enter a number in each box. 
Which line in the following spectrum would indicate the presence of a carbonyl group? a 5 b 2 c 1 d 4 e 3
Which isn't true about  13C NMR spectroscopy? a. Each distinct carbon produces a single peak  13C  NMR spectrum. b. Splitting of signals into multiple peaks is not observed in routine  13C  NMR spectra. c. Decreased electron density around an atom shields the atom from the magnetic field d. Larger mass of samples is usually required. e. 13C  spectra are usually less complex and easier to interpret than 1H NMR
Which carbon atom is most deshielded in the following molecule?
How many peaks (signals) would you expect in the broadband-decoupled  13C NMR spectrum of each of the following compounds? Example: You would see 4 peaks (signals) in 2-butanone, CH 3COCH2CH3.
Circle the most deshielded carbon in the 13C NMR spectrum of the compound shown below.
How many 13C signals will an NMR spectrometer distinguish in 1-fluoro-4-iodocyclooctane? 
Select the single best answer.Which of the highlighted carbon atoms absorbs farther downfield? (i) carbonyl carbon (ii) methylene carbon