A certain element is found on earth in the form of two isotopes. One of these has mass 39.5504 AMU and abundance of 26.57 percent. The other isotope has mass 42.7995 AMU and is present at an abundance of 73.43 percent. What is the atomic mass of this element?

Question

A certain element is found on earth in the form of two isotopes.  One of these has mass 39.5504 AMU and abundance of 26.57 percent.   The other isotope has mass 42.7995 AMU and is present at an abundance of 73.43 percent.   What is the atomic mass of this element?

ddcamp · Answer

= (Percent of isotope a)×(Mass of isotope a) + (percent of isotope b)×(mass of isotope b)

Percents are in decimal form (i.e. 74.42% = 0.7442)