Question

se adauga 20 g sare in 300 g solutie de sare cu concentratie 15 % solutia obtinuta are concentratia​

Answer 1

Răspuns:

Explicație:

md adaugat =20g sare

ms1= 300g sol.

c1= 15%

c2 =?

c1= md1 .100 : ms1

md1= c1 . ms1 : 100

md1= 15 . 300 : 100 = 45g sare

md 2 = md1 + md adaug.

md 2= 45 + 20= 65g sare

ms2 = ms1 + md adaug.

ms 2 =  300 + 20= 320g sol.

c2= md2 . 100 : ms2

c2= 65 .  100 : 320  = 20,31 %