Question

Sa se calculeze concentratia procentuala a solutiei obtinute prin
a)adaugarea a 200g apa la 100g solutie de concentratie 25%
b)Adaugarea a 5g sare la 75g solutie cu concentratia 2%

Answer 1

a) C=md/ms*100=>md=C*ms/100=25*100/100=25g 

ms final = 100+200=300g

C final = md/ms final*100 = 25/300*100 = 

b) C=md/ms*100=>md=C*ms/100=2*75/100=1,5g sare

md final = 5+1,5=6,5g

ms final = 75+1,5=76,5g

C=md final/ms final*100=6,5/76,5*100=