Mass spectrometry (molecules)

Question 1

General formula of a molecule in spectroscopy

Answer 1

M

Question 2

What is formed as the gaseous molecules are passed throught he ionization zone

Answer 2

1+ molecular ions

Question 3

On a mass spectrum graph, how does the m/a ratio of the molecule appear and its name

Answer 3

Molecular ion peak
As the peak with the highest mass (furthest right)

Question 4

M+1 peak and what causes it

Answer 4

A small peak, one unit after the M+ peak
Caused by the fact that 1.1% of carbon is the carbon 13 isotope of approximately 1 1% of molecules in a sample will have a Mr one unit greater than that calculated using 12 as Mr of C

Question 5

Fragmentation?

Answer 5

When some of the molecular IONS break down before detection into smaller fragmenst

Question 6

What are the 2 products of fragmentation of a molecular ion

Answer 6

A radical (uncharged) and a positive ion

Question 7

Which of the 2 products of fragmentation of M+ would be detected by a mass spectrometer, why

Answer 7

The ion as only 1+ charges can be detected by the ion detector

Question 8

What do the hights of fragment peaks represent

Answer 8

The likelihood of a particular fragmentation (but cant be easily predicted)

Question 9

Uses of mass spectrometry

Answer 9

Identifying the structure of unknown compounds: testing urine for banned substances in sports