Răspuns :
masa substantei dizolvate ( sare )=x
masa apei=350 g
masa solutiei ms=350 +x
c=x/ms
x / (x+350) =0.03
x=0.03*x +0.03*350
0.97 *x= 10.5
x=10.5/0.97
x=10.82 g sare
masa substantei dizolvate ( sare )=x
masa apei=350 g
masa solutiei ms=350 +x
c=x/ms
x / (x+350) =0.03
x=0.03*x +0.03*350
0.97 *x= 10.5
x=10.5/0.97
x=10.82 g sare