Organic Chemistry: Spectroscopy Basics
IR, NMR, and mass spectrometry — interpret spectra to identify organic compounds.
Study these flashcards with spaced repetition
Track your progress, master difficult cards, and export to Anki. Free to start.
Start Studying — FreeFlashcards in This Deck
In IR spectroscopy, what is the characteristic absorption range and appearance of a typical alcohol O-H stretch?
A typical alcohol O-H stretch appears as a strong, broad peak in the range of 3200–3600 cm⁻¹.
Where does the strong absorption for a carbonyl group (C=O) typically appear in an IR spectrum?
The carbonyl group typically appears as a strong, sharp peak near 1700 cm⁻¹ (usually 1650–1750 cm⁻¹).
What information does the integration of a signal in a ¹H NMR spectrum provide?
Integration represents the area under the peak, which is proportional to the relative number of hydrogen atoms contributing to that signal.
In mass spectrometry, what is the definition of the 'base peak'?
The base peak is the most intense peak in the mass spectrum (assigned 100% abundance), representing the most stable fragment ion.
According to the n+1 rule in ¹H NMR, what splitting pattern is expected for a proton with two equivalent neighboring protons?
A triplet (n=2, so 2+1=3).
What does the molecular ion peak (M+) in a mass spectrum represent?
The molecular ion peak represents the intact molecule that has lost one electron, providing the molecular weight of the compound.
How can you distinguish between an alcohol O-H and a carboxylic acid O-H using IR spectroscopy?
An alcohol O-H is broad and centered around 3300 cm⁻¹, while a carboxylic acid O-H is much broader (2500–3300 cm⁻¹) and often overlaps with C-H stretches.
What is the typical chemical shift range for aromatic protons (hydrogens on a benzene ring) in ¹H NMR?
Aromatic protons typically appear in the range of 6.5 to 8.5 ppm.
Describe the ¹H NMR splitting pattern and relative integration for an isolated isopropyl group (-CH(CH₃)₂).
An isopropyl group shows a doublet integrating to 6H (the methyls) and a septet integrating to 1H (the methine).
How does the presence of a single Chlorine atom affect the molecular ion region in a mass spectrum?
It produces an M+2 peak that is approximately one-third the height of the M+ peak due to the ³⁵Cl and ³⁷Cl isotopes.
+10 more cards — sign up to see all
Frequently Asked Questions
How many flashcards are in this Organic Chemistry: Spectroscopy Basics deck?
This deck contains 20 flashcards with a mix of difficulty levels: 6 easy, 10 medium, and 4 hard cards.
Is this flashcard deck free to use?
Yes! You can study these flashcards for free with our spaced repetition system. Create a free account to track your progress and save your study history.
Can I export these flashcards to Anki?
Pro users can export any deck to Anki (.apkg format) with one click. Free users can export to CSV. Start studying for free and upgrade when you need Anki export.
What is spaced repetition?
Spaced repetition is a study technique that shows you cards at increasing intervals based on how well you know them. Cards you struggle with appear more often, while mastered cards are shown less frequently. This is proven to be one of the most effective ways to memorize information.
Related Flashcard Decks
Ready to study?
Create a free account and start studying these flashcards with spaced repetition.
Get Started — Free