A-Level Chemistry: NMR Spectroscopy Syllabus

Overview

In A-Level Chemistry, NMR spectroscopy is mainly used to help students identify the structure of organic molecules. Students are expected to interpret both carbon-13 (13C) and proton (1H) NMR spectra.

What Students Need to Know

• NMR provides information about the different chemical environments of atoms in a molecule.
• 13C NMR shows the different carbon environments present.
• 1H NMR shows the different hydrogen (proton) environments present.
• Chemical shift is measured using the δ (delta) scale.
• Chemical shift depends on the surrounding molecular environment.
• 13C NMR spectra are usually simpler than 1H NMR spectra.

Skills Students Are Expected to Develop

• Predict the number of different carbon or proton environments in a molecule.
• Use the number of peaks to explain how many different environments are present.
• Interpret chemical shift values to identify possible atom environments.
• Use integration in 1H NMR to determine the relative number of protons in each environment.
• Apply the n + 1 rule to work out splitting patterns caused by adjacent non-equivalent protons.
• Recognise common splitting patterns such as singlets, doublets, triplets, and quartets.
• Use NMR data to suggest full or partial structures of organic molecules.

Additional Knowledge Sometimes Required

• The use of TMS (tetramethylsilane) as a standard reference.
• The use of deuterated solvents when recording spectra.
• Identification of O-H and N-H protons using D2O exchange in some specifications.
• Combining NMR evidence with IR spectroscopy and mass spectrometry to identify compounds.