Chapter 17 Mass spectrometry

Question 1

What does the mass spectrometer detect

Answer 1

the mass to charge ratio of the molecular ion which gives the molecular mass of the compound

Question 2

What do you find the molecular ion peak on mass spectrometer

Answer 2

the very last peak

Question 3

What is fragmentation

Answer 3

• in mass spectrometer some molecular ions break into smaller pieces called fragments
• these are the otehr peaks caused by fragment ions

Question 4

What is the simplest fragmentation

Answer 4

breaks a molecular ion into two species - a positivley charged fragment ion and a radical

Question 5

What are the more common fragment ions

Answer 5

• CH3+ - 15
• C2H5+ - 29
• C3H7+- 43
• C4H9+ - 57

Question 6

What does the amount that a bond stretches or bends on depend on

Answer 6

• the mass of the atoms in the bond - heavier the atoms the more sloly than lighter atoms
• the strength of the bond - stronger bonds vibrate faster than weaker bonds