Question

What's the difference between relative and percentage abundance?

What's the difference between realtive and average atomic mass? Is there a difference?

Answer 1

Relative abundance is the frequency with which "something" exists compared to a different "something". For example, you might find 1 blue bird for every 5 black birds (but you might want to compare it with with some other species).
Percent abundance is the frequency compared to the whole. For example, 1 bluebird sighted in a day versus 100 birds total seen that day is (1/100)*100 = 1%.

I don't believe there is any difference between relative and average atomic mass. All atomic masses that you find in a table are relative to 6-C-12 as well as averages of the masses of each isotope (relative to 6-C-12). You CAN calculate the atomic mass of a single isotope and that is relative to 6-C-12 but with no other isotopes added in.

Answer 2

Thank you!