We’re given the following values:
Average Atomic Mass = 10.821 amu (found in books or the internet)
Boron-10: Mass = 10.01294 amu
Boron-11: Mass = 11.00931 amu
We don’t know the percent abundance of boron but we can use the fact that the f.a. of all isotopes of an element add up to 1.
Since there are only two isotopes, this means:
Boron-10: f.a. = x
Boron-11: f.a. = 1 – x
Solving for x:
Boron has only two naturally occurring isotopes. The mass of boron-10 is 10.01294 amu and the mass of boron-11 is 11.00931 amu .
Use the atomic mass of boron to calculate the relative abundance of boron-11.
Frequently Asked Questions
What scientific concept do you need to know in order to solve this problem?
Our tutors have indicated that to solve this problem you will need to apply the Isotopes concept. You can view video lessons to learn Isotopes. Or if you need more Isotopes practice, you can also practice Isotopes practice problems.