Elemental chlorine exists as a diatomic molecule Cl2.

Question

Chlorine atoms exist in two different isotopes 35Cl and 37Cl.

In the mass spectrum of chlorine molecules,
how may peaks due to chlorine atoms would be observed? 2

how many different peaks due to the molecular ion would be observed? 3

35Cl is three times as abundant as 37Cl.
Which of the three molecular ion peaks would be least intense?
m/z 74
m/z 72
m/z 70

Answer 1

Please explain each of the question....I guessed which is not good..I need to understand.........

Answer 2

I found this site that does a really neat job of explaining the five lines ones gets from Cl2. Scroll down from the top until you get to the Cl2 part.
http://www.chemguide.co.uk/analysis/masspec/elements.html