17.1

Question 1

When organic compound placed in mass spectrometer, forms positive ion called ____________

Answer 1

Molecular ion

Question 2

Mass spectrometer detects the __________ of the molecular ion

Answer 2

M/z

Mass to charge ratio

Question 3

Find molecular mass how?

Answer 3

molecular ion peak has to be located - clear peak at highest m/z value (look at the very right side of mass spectrum)

Question 4

Why see small peak after molecular ion peak on mass spectrum?

Answer 4

1.1% carbon is carbon-13 so very few number of molecules will have slightly larger mass/charge ratio

Question 5

What is fragmentation?

Answer 5

Process in mass spectrometry that causes positive ion to split into smaller pieces, one of which is a positive fragment ion

Question 6

Apart from the molecular ion, what are all the other peaks in a mass spectrum?

Answer 6

Fragment ions

Question 7

Simplest fragmentation breaks molecular ion into…

Answer 7

2 species, positive charge fragment ion and radical

Radical uncharged, so not picked up in mass spectrum

Question 8

How to use m and m+1 peak to work out number carbon atoms?

Answer 8

(Height of m+1/height of m) x 100