Question

Din 150 g soluție de concentrație 5 % s-au evaporat 50 g apa . Determinați concentratia finala.




Va rog repede!!!

Answer 1

[tex] \frac{md}{ms} = \frac{c}{100}=\ \textgreater \ md= \frac{ms*c}{100}\ \textless \ =\ \textgreater \ md= \frac{150*5}{100} \\\\ =\ \textgreater \ md=1,5*5=\ \textgreater \ md=7,5 m_{H2O}=ms-md~ \\ m_{H_2O}=150-7,5\\\\\bold{m_{H_2O}=142,5grame}\\\\ m_{H2O~ramas}=142,5-50\\\\ \bold{m_{H2O~ramas}=92,5grame}\\\\ ms=92,5+7,5 \\\\\bold{ms=100g}\\\\ \frac{c}{100} = \frac{md}{ms}\\\\c= \frac{100*7,5}{100}\\\\\bold{c=7,5 }[/tex]