if the heaviest isotope is more abundant, and the other two isotopes were less abundant, what would happen to the atomic mass of beanium? why?

Question

This is for the beanium lab and I have no idea what the answer is, I'm totally lost.

Answer 1

By increasing the abundance of one isotope, there is greater "impact" on the average atomic mass, so it is likely that the average atomic mass would increase. It would be helpful to have some numbers to check for this effect, so maybe you can try them from whatever data you might have on the beanium lab.

Answer 2

The average atomic mass is calculated using this formula Average Atomic Mass=P1P1+P2M2+......+PnMn 

P is the percent of abundance, M is the corresponding isotope. P1, P2......Pn add up to 100%. So if a heaviest mass is more abundunt, the lighter masses are relatively less abundant. This will make the average atomic mass increase in value.