Question

Boron has an average atomic mass of 10.81. One isotope of boron has a mass of 10.012938 and a relative abundance of 19.80%. The other isotope has a relative abundance of 80.20%. What is the mass of that isotope? Report to two decimal places. amu

Answer 1

11.01 amu

Step-by-step explanation:

19.8% • 10.012938 = 1.982561724

10.81 - 1.982561724 = 8.827438276

8.827438276/80.2% = 11.0067808928