Question

Cate grame de Ca se gasesc in 250g CaCO3 de puritate 80%?

Answer 1

$m_{CaCO_3 \ pur}=\frac{80*250g}{100}=200g$

$M_{CaCO_3}=40+12+3*16=100g/mol$

$100g \ CaCO_3..........40g \ Ca$

$200g \ CaCO_3...........x \ g \ Ca$

$\frac{100}{200}=\frac{40}{x}$

$x=\frac{200*40}{100}=80g$