Question

Aflati concentratia procentuala a unei solutii obtinute prin amestecarea a 400g solutie de zahar cu c1= 20%, cu 300g solutie de zahar cu c2= 40% si 300g apa.

Answer 1

c=mdx100/ms----> md=cxms/100

ms1= 400g

c1= 20%------.> md1= 80g

ms2=300g

c2=40%----> md2=120g

c3= md3x100/ms3    unde   md3=md1+md2=200g

                                               ms3= ,s1+ms2+m,apa=1000g

c3= 200x100/.1000=........................calculeaza !!!!