...........25,5 g.............................x
Cu + AgNO3--> CuNO3 + Ag
...........170 g............................108 g
[tex]c = \frac{md}{ms} \times 100 \\ md = \frac{c \times ms}{100} \\ md = \frac{30 \times 85}{100} = 25.5 \: g[/tex]
[tex]x = \frac{25.5 \times 108}{170} = 16 . 2 \: g[/tex]