Question

Se considera o solutie formata din 25 grame sare si 275 grame apa
a)Calculeaza concentratia acestor solutii.
b)Peste solutia initiala se adauga 25 grame apa.Calculati c2
c)Peste solutia initiala se adauga 25 grame sare.calculati c3
d)Peste solutia initiala se adauga 200grame saramura de concentratie 20%.Calculati c4
e)Din solutia initiala se evapora 50 de grame apa.Calculati c5

Answer 1

C=mdx100/ ms,         unde ms=md+m,apa
md= cxms/100

c1= 25x100/ (25+275)= 8,33%
c2=25x100/(300+25)=---------------------------
c3=(25+25)x100/ (300+25)=---------------------
c4= ( c1md1+cxmd)/(ms1+ms)=>(0,0833x300+0,2x200)/(300+200)------------
c5=25x100/ (300-50)=-------------------------

calculeaza c2,c3,c4,c5 !!!!