Silver has an atomic mass of 107.868 amu. The Ag-109 isotope (108.905 u) is 48.16%. What is the atomic mass of the other isotope?

The element bromine is Br2, so the mass of a Br2 molecule is the sum of the mass of its two atoms. Bromine has two isotopes. The mass spectrum of Br2 produces three peaks with relative masses of 157.836, 159.834, and 161.832, and relative heights of 6.337, 12.499. and 6.164, respectively. (a) What isotopes of bromine are present in each of the three peaks? (b) What is the mass of each bromine isotope? (c) What is the average atomic mass of bromine? (d) What is the abundance of each of the two bromine isotopes?

2.75 Chlorine has only two isotopes, one with mass 35 and the other with mass 37. One is present at roughly 75% abundance, and the atomic weight of chlorine on a periodic table is 35.45. Which must be the correct mass spectrum for chlorine?

The atomic mass of boron (B) is given in the periodic table as 10.81, yet no single atom of boron has a mass of 10.81 u. Explain.