Answer
207.24 amu
Work Step by Step
To calculate the average atomic mass we add the products of the relative abundance and the mass of each isotope together.
Isotope 1: mass= 204 amu (1.4%)
Isotope 2: mass= 206 amu (24.1%)
Isotope 3: mass= 207 amu (22.1%)
Isotope 4: mass= 208 amu (52.4%)
= 204 (1.4%) + 206 (24.1%) + 207 (22.1%) + 208 (52.4%)
= 204 (0.014) + 206 (0.241) + 207 (0.221) + 208 (0.524)
= 207.24 amu
