Question

1. solutie cu masa 60g si concentrație 40% se amesteca cu o solutie de masa de 300g si concentratia de C2 =20% .
Sa se afle concentratia finala .

2. Se amesteca o solutie cu ms=20g si concentratia 40% cu ms = 50g si concentratia 20% .
Care va fi concentratia finala

3. Sa se determine concentratia solutiei din amestecul a trei solutii care au concentratia C1=41% , C2=12% , C3=18% si masele solutilor ms1= 430g , ms2=37g si ms3=70g
Sa se afle C final ??

Va rog e urgent si vreau desfasurat cu toate calculele etc

Answer 1

1.ms=20g                                ms3=ms1=ms2
c=40%                                    ms3=20+50
ms2=50g                                ms3=70g
c2=20%                                  md1=c1xms1/100
--------------                              md1=20x40/100
c3=?                                       md1=800/100=8g
                                               md2=c2xms2/100
                                               md2=20x50/100
                                               md2=1000/100=10g
                                               md3=md1+md2
                                               md3=8+10
                                               md3=18g
                                               c3=md3/ms3 x 100
                                               c3=18/70 x 100

                                               c3=1800/700=18/7=18:7=2,5714