Question

Cần lấy bao nhiêu gam CuSO4.5H2O vào bao nhiêu gam dd CuSO4 16% để pha trộn thành 300g dd CuSO4 48%.

Answer 1

\(m_{CuSO_4\cdot5H_2O}=a\left(g\right)\)

\(m_{dd_{CuSO_4\left(16\%\right)}}=b\left(g\right)\)

\(\Rightarrow m_{dd_{CuSO_4\left(48\%\right)}}=a+b=300\left(g\right)\left(1\right)\)

\(m_{CuSO_4}=\dfrac{a}{250}\cdot160=0.64a\left(g\right)\)

\(m_{CuSO_4\left(16\%\right)}=0.16b\left(g\right)\)

\(m_{CuSO_4\left(48\%\right)}=300\cdot48\%=144\left(g\right)\)

\(\Rightarrow0.64a+0.16b=144\left(2\right)\)

\(\left(1\right),\left(2\right):a=200,b=100\)