Mass Spectra Examples & Calculations

Question 1

What does the mass spectra show?

Answer 1

it shows the relative abundances of the different isotopes present (and their masses

Question 2

What is the percentage abundance?

Answer 2

what percentage of the sample is what type of isotope

Question 3

What is the m/z - mass to charge ratio

Answer 3

it is the isotopic masses

Question 4

Example - Calculate the Ar of Chlorine

percentage abundance for Cl 35 - 75%
Cl 37 - 25%

m/z for Cl 35 - 35

m/z for Cl 37 - 37

Answer 4

Ar = (7535) + (2537) / 100 = 35.5 g.mol^-1