Question

25. An element has two stable isotopes. One isotope has a mass of 62.9 amu and an abundance of 69.2%.

The other isotope has a mass of 64.9 amu and an abundance of 30.8%. Show how to calculate the
average atomic mass of this element and give the value with the correct units and significant figures.
Don't just give the answer. Show your work
Show work:
Answer:

Answer 1

Average Atomic Mass= 63.5 amu

Step-by-step explanation:

Average Atomic Mass Equation:

(Mass 1)(% Abundance) +(Mass 2)(% Abundance)

Plug in Variables:

Make sure to convert the percentages into decimals. (Left two places)

Use the order of operations when solving.

(62.9)(0.692) + (64.9)(0.308) = AAM

Multiply each side

43.5268 + 19.9892 = AAM

Add the products together

63.516 = AAM

Add proper unit and satisfy the 3 significant figures needed

63.5 amu