What is the isotopic composition of strontium metal?

1 Answer
Feb 22, 2017

Because you have misreported the isotopic composition.

Explanation:

This site reports the isotopic composition of strontium as #""^84Sr, 0.56%; ""^86Sr, 9.86%;""^87Sr, 7.00%;""^88Sr, 82.58%#. The weighted average of the isotopes in #87.62(1)*"amu"#. The quoted atomic mass should be near to the weighted average of the isotopes.

Since for strontium, #Z=38#, there are #84-38=??*"neutrons"# in the #""^84Sr# isotope.