posted by Anonymous .
In 1928, 1.0 g of Re was isolated from 660 kg of the ore molybenite. The percent by mass of this element in the molybenite was:
1.5 x 10 ^-4 %
How to set this up, given that 600 kg equals 660,000 g. And Avogadro's number 6.022x10^23?
You didn't ask a question. By the way, the ore is molybDenite and the element, Mo, is molybDenum (without the capital letters, of course).