Lecture 2: Lab Techniques 1

Question 1

Mass spectrometry

Answer 1

1. Finds molecular weight of an unknown compound and which atoms are in that compound
2. Steps: vaporizes and ionizes sample, magnetic field changes momentum of each particle and particles are detected and deflection is messed
   2a. Lone pairs are easiest to eject
3. The more H, the bigger the m/z value (x axis)

Question 2

Spectroscopy

Answer 2

1. Absorb, emit and scattering light to produce a unique spectra
   1a. Electron to higher energy: absorption of a photon
   1b. Electron to lower energy: emitting photon

Question 3

IR spectroscopy

Answer 3

1. Highest frequency: hydrogen bond -> triple bond -> double bond -> single bond

Question 4

NMR spectroscopy

Answer 4

1. 1H and 13C have a spin that can be measured because they generate a dipole moment
2. NMR spectra
   2a. High NMR spectrum: high frequency, high chemical shift, deshielded, downfield
   2b. Low NMR spectrum: low frequency, low chemical shift, shielded, upfield
3. Intensity: more intense when there are more hydrogens
4. Singlet: if no hydrogen neighbors