To calculate the atomic mass of an element, the percent
abundance of etch isotope is needed. ?

List the known and unknown quantities and plan the problem. Change each percent abundance into decimal form by dividing by 100. Multiply this value by the atomic mass of that isotope. Add together for each isotope to get the average atomic mass

Explanation:

if you mean hydrogen and oxygen then water is the product

space exploration has led to the development and technological improvement of many everyday items. (if this answer is wrong i will find the right answer) : )