Interpreting Mass Spectrum

Question 1

What does y-axis of mass spectrum give?

Answer 1

Abundance of ions

Question 2

For each element, what does the height of each peak give?

Answer 2

Relative isotopic abundance

Question 3

What is m/z?

Answer 3

Mass/charge

Question 4

How do you calculate Ar from mass spectrum(no %)?

Answer 4

1) For each peak, multiply x-axis with y-axis
2) Add up totals
3) Divide by sum of relative abundances

Question 5

How can a mass spectrum be used to identify relative molecular mass?

Answer 5

1) Molecular ion is formed when 1 electron is removed from molecule
2) Gives peak with mass/charge ratio equal to rfm of molecule

Question 6

Why do isotopes have similar chemical properties?

Answer 6

Same number of electrons in outer shells, electrons take part in chemical reactions

Question 7

Equation for Ar

Answer 7

(Σ% abundance x mass of isotope)/ 100