Question

Peste 200 grame de solutie de concentratie 15% se adauga 150 grame apa. Ce concentratie va avea solutia obtinuta?

Answer 1

ms1=200g
c1=15%
ma=150g apă adăugată$c1 = \frac{md}{ms1} \times 100 \\ md = \frac{c1 \times ms1}{100} \\ md = \frac{15 \times 200}{100} = 30g$ms=ms1+ma=200+150=350g
$c = \frac{md}{ms} \times 100 \\ c = \frac{30}{350} \times 100 = 8.57\%$