Antimony is used in infrared devices and lead storage batteries. The element occurs in two naturally occurring isotopes, one with mass
120.904 amu and the other with mass 122.904 amu. Use the atomic mass of antimony from the periodic table to calculate the natural abundance of each isotope

Question

Antimony is used in infrared devices and lead storage batteries. The element occurs in two naturally occurring isotopes, one with mass 
120.904 amu and the other with mass 122.904 amu. Use the atomic mass of antimony from the periodic table to calculate the natural abundance of each isotope

anonymous · Answer

I got x of 0.572, how would i calculate the percent abundance

aaronq · Answer

it's just a weighted average, you have the equations:

$\sf Mass~on ~periodic ~table=\sum(abundance*Isotope~mass) $

$\sf 1=Sb_{120}~abundance+Sb_{122}~abundance$