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A fictitious element, Blackboardium, has two naturally occurring isotopes. Bb-301 is 31.6% abundant. Bb-304 is 68.4% abundant. What is the average atomic mass of Blackboardium?

User Sml
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Answer: To find the average atomic mass of Blackboardium, we need to use the formula for weighted average of the atomic masses of its isotopes, multiplied by their relative abundances. The formula is:

Average atomic mass = (p1m1 + p2m2 + … + pnmn) / 100%

where p is the percentage abundance of each isotope, and m is the atomic mass of each isotope.

Since Blackboardium has two isotopes, Bb-301 and Bb-304, we can plug in the values given in the question:

Average atomic mass = (31.6 * 301 + 68.4 * 304) / 100%

Average atomic mass = (9511.6 + 20781.6) / 100%

Average atomic mass = 30293.2 / 100%

Average atomic mass = 302.932 amu

Therefore, the average atomic mass of Blackboardium is 302.932 amu.

User Bobthecow
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