Question

Se amesteca 45 g solutie de sare cu concentratie de 12 la suta cu o solutie de 80g cu cncentratie 30 la suta.Ce concentratie are solutia?Ce concentratie va avea solutia finala daca mai adăugăm inca 250ml de apa?Am mare nevoie.

Answer 1

ms1=45g

c1=12%

ms2=80g

c2=30%

c=?

cf=?

c=md/ms×100

md1=c1×ms1/100 = 12×45/100=5.4 g

md2=80×30/100= 24g

md=md1+md2= 5.4+24=29.4 g

ms=ms1+ms2= 45+80=125g

c=29.4×100/125 = 23.52%

cf=md/md+mapa×100= 29.4×100/29.4+250=2940/279.4=10.52%