ms1=300g
c1=10%
ms2=200g
c2=20%
mapa =200g
cf=?
-se afla md 1 si md2 pentru cele doua sol.
md1=c1 . ms1 : 100
md1=10 . 300 : 100=30 g
md2= c2 . ms2 : 100
md2=20 . 200 : 100=40 g
md final=30 +40=70 g HCl
-se afla ms final
ms f= 300g+ 200g + 200g apa=700g
-se afla c final
c f= md f .100 : ms f
c f= 70 .100 : 700=10 %