Question

Do 250ml roztworu 90% o gestosci 2g/cm3 dodano 3l roztworu 10% o gestosci 0,5g/cm3. Oblicz stezenie powstalego roztworu.

Answer 1

v₁=250cm³
d₁=2g/cm³
m₁=v₁*d₁
m₁=250*2
m₁=500g

v₂=3000cm³
d₂=0,5g/cm³
m₂=v₂*d₂
m₂=3000*0,5
m₂=1500g

500g 90% .................. x-10
..................... x%
1500g 10% ................ 90-x

500/1500 = x-10/90-x
500(90-x) = 1500(x-10)
45000-500x = 1500x-15000
2000x = 60000
x = 30%