Final answer:
To calculate the average atomic mass of element X, multiply the abundance of each isotope in decimal form by its atomic mass and sum the results, yielding an average atomic mass of 207.2156 amu for element X.
Step-by-step explanation:
To calculate the average atomic mass of element X, use the abundance of each isotope as a fractional weighting factor. Convert the percentage abundance of each isotope into a decimal by dividing by 100, then multiply by the isotope's atomic mass (in amu). Finally, add together the products for each isotope to find the average atomic mass of the element.
Let's perform the calculations for element X:
- X-204: (0.014 × 203.973 amu) = 2.85562 amu
- X-206: (0.241 × 205.974 amu) = 49.64034 amu
- X-207: (0.221 × 206.976 amu) = 45.74296 amu
- X-208: (0.524 × 207.977 amu) = 108.97668 amu
Add these values to get the average atomic mass for element X:
Average Atomic Mass
= 2.85562 amu + 49.64034 amu + 45.74296 amu + 108.97668 amu = 207.2156 amu