Question

Ile wody należy odparować z 50g 12% wodnego roztworu azotanu(V) sodu, aby otzrymać 20% roztwór tej soli?

Answer 1

mr = 50g
Cp = 12%

ms = mr*Cp/100 = 50*12/100 = 6g
MH2O = 50g - 6g = 44g H2O

Cp = 20%
ms = 6g
mr = ms *100/Cp

mr = 6*100/20 =  30g

m H2O = 30g - 6 = 24g

44-24 = 20g

Należy odparować 20g H2O.

 

Answer 2

 

Cp1 = 12%
mr1= 50g

ms = Cp x mr / 100%
ms = 12% * 50g / 100% = 6g
Cp2 = 20%
mr2 = ms x 100% / Cp
mr2 = 6g * 100% / 20% = 30g

50g - 30g = 20g

 

Należy odparować 20g H2O