Hello there!
If we assume that the quartz rock is pure silicon dioxide, we only need to use a conversion factor to go from grams of quartz rock (SiO₂) to grams of Silicon. The conversion factor uses the molar mass of SiO₂ (60,08 g/mol) and the atomic mass of Silicon (28,0855 g/mol):
[tex]500 g SiO_2* \frac{1 mol SiO_2}{60,08 g SiO_2}* \frac{1 mol Si}{1 mol SiO_2}* \frac{28,0855 g Si}{1 mol Si}=233,73 g Si[/tex]
So, 233,73 grams of Silicon can be obtained.
Have a nice day!
