Ce concentratie are solutia obtinuta prin amestecarea a 500g solutie de concentratie 10%, cu 0,4 Kg solutie de concentratie 20% si 100g apa ?

Răspuns :

c3=md3x100/ms3,  unde  

md3= md1+md2          ms3= ms1+ms2+ m,apa

md1= c1xms1/100= 500x10/100g=50g

md2= 400x20/100= 80g

md3=130g


ms3= 500+400+100=>1000g

c3= 130x100/1000=.......................calculeaza !!!!!