1. Boron has 2 naturally occuring isotopes, which have masses10.0129 and 11.0093 amu, respectively. Given the average atomic mass of boron (10.81amu), determine the % abundance of each isotope.
2. The 2 naturally occuring isotopes of antimony,121Sb (57.21%) and 123Sb (42.79%), have masses of 120.904 and 122.904 amu, respectively. What is the average atomic mass of Sb?