Question

An ore contains 1.34% of the mineral argentite, `Ag_(2)S`, by mass. How many gram of this ore would have to be processed in order to obtain 1.00 g of pure solid silver, Ag?
A. `74.6 g`
B. `85.7 g`
C. `107.9 g`
D. `134.0 g`

Answer 1

Correct Answer - C
100 g ore = 1.34 g of `Ag_(2)S`
Molar mass of `Ag_(2)S = 248 mol^(-1)`
248 g of `Ag_(2)S = 2xx108g of Ag = 216 g of Ag 1.00 g of Ag`
`= 1.00 g of Agxx((248AG_(2)S)/(216gAg))xx((100gore)/(1.34gAg_(2)S))`
`= 85.68 g = 85.7 g`