Question

Ce cantitae de apa trebuie adaugata peste 400 g solutie de C=25% pentru a o dilua pana la C=10%?
Dau COROANA . VA ROG

Answer 1

C=md*100/ms
md=C*ms/100
md=25*400/100
md=100g

C2=md*100/ms2
ms2=md*100/C2
ms2=100*100/10
ms2=1000g
m,apa=ms2-md
m,apa=1000-100
m,apa=900g

Answer 2

100g..............25.g 
400g           md=100 g

100g                             10g
ms2=1000 g                  100

mH2O=ms2-ms1=1000-400=600 g