Y2 Structural Determination (O)

Question 1

Changes in vibration are caused by the absorption of

Answer 1

infrared radiation

Question 2

Changes in nuclear spins are caused by the absorption of

Answer 2

radiowaves

Question 3

Changes in rotation are caused by the absorption of

Answer 3

microwaves

Question 4

Infrared - all bonds vibrate at a charateristic frequency, which depends on

Answer 4

• Mass of the atoms
  -strength of the bond
• Types of vibration

Question 5

Good excuse for any infrared question

Answer 5

fingerprint region (less than 1500 wavenumber)

Question 6

Wavenumber is

Answer 6

• 1 over wavelength in cm

therefore units cm-1

Question 7

Mass spectrometry is used to

Answer 7

• determine RAM
• find relative molecular mass of an organic substance
• Distinguish between several molecules of the same molecular mass
• Determine the structure of an organic molecule through fragmentation patterns

Question 8

Axis on a mass spectrometry graph

Answer 8

• y is relative abundance (highest peak often given a value of 100, this is labled the base peak)
• x is mass to charge ratio (watch out as can be doubly charged)