PTHH: \(Zn+CuSO_4\rightarrow ZnSO_4+Cu\)

Phản ứng trên là phản ứng thế

Ta có: \(n_{CuSO_4}=\dfrac{32\cdot10\%}{160}=0,02\left(mol\right)=n_{Cu}=n_{Zn}=n_{ZnSO_4}\)

\(\Rightarrow\left\{{}\begin{matrix}m_{Zn}=0,02\cdot65=1,3\left(g\right)\\m_{Cu}=0,02\cdot64=1,28\left(g\right)\\m_{ZnSO_4}=0,02\cdot161=3,22\left(g\right)\\\end{matrix}\right.\) \(\Rightarrow C\%_{ZnSO_4}=\dfrac{3,22}{32+1,3-1,28}\cdot100\%\approx10,06\%\)

Ta có: \(m_{CuSO_4}=40.10\%=4\left(g\right)\Rightarrow n_{CuSO_4}=\dfrac{4}{160}=0,025\left(mol\right)\)

PT: \(Zn+CuSO_4\rightarrow ZnSO_4+Cu\)

Theo PT: \(n_{Zn}=n_{ZnSO_4}=n_{Cu}=n_{CuSO_4}=0,025\left(mol\right)\)

\(\Rightarrow m_{Zn}=0,025.65=1,625\left(g\right)\)

Ta có: m _{dd sau pư} = 1,625 + 40 - 0,025.64 = 40,025 (g)

\(\Rightarrow C\%_{ZnSO_4}=\dfrac{0,025.161}{40,025}.100\%\approx10,056\%\)

PTHH : \(Zn+CuSO_4\rightarrow ZnSO_4+Cu_{\downarrow}\)

\(a.Zn+CuSO_4->ZnSO_4+Cu\)

b. m Zn giảm vì sau phản ứng tạo Cu (M = 64), M(Cu) < M(Zn) = 65 nên khối lượng lá Zn tăng.

\(m_{Zn\left(Pư\right)}=65x\left(g\right)\\ m_{Cu}=64x\left(g\right)\\c.\Delta m_{rắn}=25-24,96=65x-64x\\ x=0,04mol\\ m_{Zn\left(Pư\right)}=65x=2,6g< 25g\Rightarrow Zn:hết\\d. n_{CuSO_4}=160x=6,4g\)

\(m_{ZnSO_4}=\dfrac{241,5.10}{100}=24,15\left(g\right)=>n_{ZnSO_4}=\dfrac{24,15}{161}=0,15\left(mol\right)\)

PTHH: 2Al + 3ZnSO₄ --> Al₂(SO₄)₃ + 3Zn

_____0,1<----0,15-------->0,05----->0,15

=> m_Al = 0,1.27 = 2,7(g)

=> m_Zn = 0,15.65=9,75(g)

b) mdd sau pư = 2,7 + 241,5 - 9,75 = 234,45(g)

=> \(C\%\left(Al_2\left(SO_4\right)_3\right)=\dfrac{0,05.342}{234,45}.100\%=7,294\%\)

mAgNO3=5,1g

=> nAgNO3=0,03mol

PTHH: Zn+  2AgNO3=>Zn(NO3)2+2Ag

          0,06   <-0,03           ->0,03  ->0,06

mZn đã dùng:m=0,06.65=3,9g

a) Pứ thế

b) nCuSO4 = 0,02 mol

mZn = 0,02 . 65 = 1,3 (g)

c) mdd sau = 1,3 + 32 - 0,02 . 64 = 32,02g

C% ZnCl2 = 10,056%