50 gam dung dich BaCl2 10% có:
\(m_{BaCl_2}=\dfrac{10.50}{100}=5\left(g\right)\)
70 gam dung dịch BaCl2 20% có:
\(m_{BaCl_2}=\dfrac{20.70}{100}=14\left(g\right)\)
Sau khi trộn thì:
\(m_{ddsau}=50+70=120\left(g\right)\)
\(m_{BaCl_2\left(sau\right)}=5+14=19\left(g\right)\)
\(\Rightarrow C\%_{BaCl_2\left(sau\right)}=\dfrac{19}{120}.100\%=15,83\%\)