Question

Se amesteca 500 g de saramura cu concentratia de 30% cu 300 g de saramura cu concentratia de 10% cu 200 g apa.Calculati concentratia procentuala a solutiei obtinute prin amestecare.

Answer 1

ms1=500g

c1=30%

ms2=300g

c2=10%

+mH2O=200g

c/100=md/ms ==> c1/100=md1/ms1 ===> md1= c1 x ms1 / 100

=> md1=30 x 500 / 100 = 150 g pur

md2= c2 x ms2 / 100 ==> md2= 10 x 300 / 100 = 30 g pur

ms(final)=ms1+ms2+m H2O

ms(f)=500+300+200=1000 g

md(f)=md1+md2=180 g

C(final)/100 = md(final)/ms(final) ==> C(final) = md(final) x 100 / ms(final)

C(final) = 180 x 100 / 1000 ==> C(final) = 18%