To calculate the relative atomic mass of boron, you need to consider the isotopic composition of boron and the atomic masses of its isotopes. Boron has two stable isotopes: boron-10 and boron-11. Here's the calculation:
Determine the isotopic composition: The isotopic composition refers to the relative abundance of each isotope in nature. For boron, approximately 19.9% is boron-10 and 80.1% is boron-11.
Retrieve the atomic masses: Look up the atomic masses of boron-10 and boron-11 from the periodic table or other reliable sources. The atomic mass of boron-10 is approximately 10.012 amu, and the atomic mass of boron-11 is approximately 11.009 amu.
Calculate the relative atomic mass: Multiply the atomic mass of each isotope by its relative abundance (as a decimal), and then sum the results.
Relative Atomic Mass = (Atomic Mass of Isotope A × Abundance of Isotope A) + (Atomic Mass of Isotope B × Abundance of Isotope B)
Relative Atomic Mass of Boron = (10.012 amu × 0.199) + (11.009 amu × 0.801)
Performing the calculation:
(10.012 × 0.199) + (11.009 × 0.801) = 2.001188 + 8.804809
Relative Atomic Mass of Boron ≈ 10.805 amu
Therefore, the relative atomic mass of boron is approximately 10.805 amu.