Question

Oblicz,ile gramów wody należy dodać do 250 g 6-procentowego octu, by otrzymać 3-procentowy roztwór

Answer 1

Cp = 6 %
mr = 250 g
ms = ?

Cp=ms/mr*100%

ms=mr*Cp/100%= 250*6/100=15
ms = 15 g

Cp = 3%
ms = 15 g
mr = ?
3% = 15g*100 / mr
mr = 500 g

500g-250 g = 250 g H20

Answer 2

250g 6% ...................3-0=3
.....................3%
xg 0%....................... 6-3=3
250/x = 3/3
3x = 250*3
x = 250g wody