Question

Peste 150 g sirop de concentratie 10% se adauga 20 g zahar, 200 g apa si 100 g sirop de concentratie 20%. Determinati concentratia solutiei finale !

Answer 1

Calculam masele de zahar si apa, din solutiile initiale
c/100=md/ms => md=c*ms/100
md1=c1*ms1/100=10*150/100=15g zahar
md2=c2*ms2/100=20*100/100=20g zahar
mzaharfinal=md1+md2+mzahar=15+20+20=55g
msfinal=ms1+ms2+mapa+mzahar=150+100+200+20=470g solutie
cf=mdf*100/msf=55*100/470=11,70%