Question

ce concentratie are solutia obtinuta prin amestecarea a 200g solutie de concentratie 10% cu 400g solutie de concentratie 20%?

Answer 1

C1=10%
ms1=200g 
c2=20%
ms2=400 g
c final=?
md1=c1*ms1/100=10*200 g/100=20 g
md2=c2*ms2/100=20*400/100=80 g
md final=md1+md2= 20g +80g =100g
msfinal=ms1+ms2=200g+400g =600g
cfinal=mdfinal/msfinal*100= 100/600*100=16,66 %

Answer 2

md=md1+md2

$c1= \frac{md_{1} *100 }{ ms_{1} }$

md1=[tex] \frac{200*10}{100} = 20 g [/tex]

$c2= \frac{md_{2} *100 }{ ms_{2} }$

md2=$\frac{400*20}{100} = 80 g$

md=20+80=100 g
ms=ms1+ms2= 200+400=600g

$c= \frac{md*100}{ms} = \frac{100*10}{600} =16.666$ %