a, \(n_{Cu\left(OH\right)_2}=\dfrac{0,49}{98}=0,005\left(mol\right)\)

Chất kết tủa là Cu(OH)₂

PTHH: 2NaOH + CuSO₄ → Na₂SO₄ + Cu(OH)₂ ↓

Mol:       0,01                                            0,005

b, \(C_{M_{ddNaOH}}=\dfrac{0,01}{0,02}=0,5M\)

\(2NaOH+CuSO_4\rightarrow Na_2SO_4+Cu\left(OH\right)_2\downarrow\)

Kết tủa thu được: \(Cu\left(OH\right)_2\downarrow\)

\(n_{Cu\left(OH\right)_2}=\dfrac{0,49}{98}=0,005mol\)

\(\Rightarrow n_{NaOH}=2n_{Cu\left(OH\right)_2}=2\cdot0,005=0,01mol\)

\(C_M=\dfrac{0,01}{\dfrac{20}{1000}}=0,5M\)

Đổi 200ml= 0,2l

Khối lượng đồng bám vào \(=203,2-200=3,2\left(g\right)\)

Đặt số mol của đồng là x

\(Fe+CuSO_4\rightarrow FeSO_4+Cu\)

x_____ x______ x_________ x

Ta có : \(64x+56x=3,2\)

\(\rightarrow8x=3,2\rightarrow x=0,4\)

\(\rightarrow m=0,4.46=22,4\left(g\right)\)

\(\rightarrow CM_{CuSO4}=\frac{0,4}{0,2}=2M\)

\(n_{CuSO_4}=\dfrac{200.16\%}{160}=0,2\left(mol\right)\)

PTHH :

\(CuSO_4+2NaOH\rightarrow Cu\left(OH\right)_2\downarrow+Na_2SO_4\)

0,2              0,4                  0,2               0,2 

\(m_{NaOH}=0,4.40=16\left(g\right)\)

\(m_{ddNaOH}=\dfrac{16.100}{10}=160\left(g\right)\)

\(c,m_{Na_2SO_4}=0,2.142=28,4\left(g\right)\)

\(m_{ddNa_2SO_4}=200+160-\left(0,2.98\right)=340,4\left(g\right)\)

\(C\%_{Na_2SO_4}=\dfrac{28,4}{240,4}.100\%\approx8,34\%\)

\(d,PTHH:\)

\(Cu\left(OH\right)_2\underrightarrow{t^o}CuO+H_2O\)

0,2               0,2 

\(m_{CuO}=0,2.80=16\left(g\right)\)

a, \(CuSO_4+2NaOH\rightarrow Cu\left(OH\right)_2+Na_2SO_4\)

b, \(m_{CuSO_4}=200.16\%=32\left(g\right)\Rightarrow n_{CuSO_4}=\dfrac{32}{160}=0,2\left(mol\right)\)

\(n_{NaOH}=2n_{CuSO_4}=0,4\left(mol\right)\Rightarrow m_{ddNaOH}=\dfrac{0,4.40}{10\%}=160\left(g\right)\)

c, \(n_{Cu\left(OH\right)_2}=n_{Na_2SO_4}=n_{CuSO_4}=0,2\left(mol\right)\)

\(\Rightarrow C\%_{Na_2SO_4}=\dfrac{0,2.142}{200+160-0,2.98}.100\%\approx8,34\%\)

d, \(Cu\left(OH\right)_2\underrightarrow{t^o}CuO+H_2O\)

\(n_{CuO}=n_{Cu\left(OH\right)_2}=0,2\left(mol\right)\Rightarrow m_{CuO}=0,2.80=16\left(g\right)\)

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

Phản ứng trên là phản ứng thế

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

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

PTHH: \(Fe+CuSO_4\rightarrow FeSO_4+Cu\)

Đặt \(n_{Fe\left(phản.ứng\right)}=x\left(mol\right)=n_{Cu\left(tạo.ra\right)}\)

\(\Rightarrow64x-56x=0,8\) \(\Rightarrow x=0,1\) \(\Rightarrow\left\{{}\begin{matrix}m_{Fe\left(phản.ứng\right)}=0,1\cdot56=5,6\left(g\right)\\m_{Cu\left(tạo.ra\right)}=0,1\cdot64=6,4\left(g\right)\end{matrix}\right.\)

\(Đặt:n_{Fe}=a\left(mol\right);n_{Al}=b\left(mol\right)\left(a,b>0\right)\\ Kim.loại.còn.lại.sau.p.ứ:Cu\\ n_{Cu}=\dfrac{25,4}{64}=0,4\left(mol\right)\\ a,PTHH:Fe+CuSO_4\rightarrow FeSO_4+Cu\\ 2Al+3CuSO_4\rightarrow Al_2\left(SO_4\right)_3+3Cu\\ \Rightarrow\left\{{}\begin{matrix}56a+27b=11\\a+1,5b=0,4\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}a=0,1\\b=0,2\end{matrix}\right.\\b, \%m_{Fe}=\dfrac{0,1.56}{11}.100\approx50,909\%\\ \%m_{Cu}\approx100\%-50,909\%\approx49,091\%\\ c,V_{ddsau}=V_{ddCuSO_4}=0,2\left(l\right)\\ C_{MddFeSO_4}=\dfrac{0,1}{0,2}=0,5\left(M\right);C_{MddAl_2\left(SO_4\right)_3}=\dfrac{0,2:2}{0,2}=0,5\left(M\right)\\ d,C_{MddCuSO_4}=\dfrac{a+1,5b}{0,2}=2\left(M\right)\)

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

a. PTHH: \(CuSO_4+2NaOH--->Na_2SO_4+Cu\left(OH\right)_2\downarrow\)

b. Đổi 100ml = 0,1 lít

Ta có: \(n_{Cu\left(OH\right)_2}=\dfrac{9,8}{98}=0,1\left(mol\right)\)

Theo PT: \(n_{CuSO_4}=n_{Cu\left(OH\right)_2}=0,1\left(mol\right)\)

=> \(m_{CuSO_4}=0,1.160=16\left(g\right)\)

c. Theo PT: \(n_{NaOH}=2.n_{CuSO_4}=2.0,1=0,2\left(mol\right)\)

=> \(C_{M_{NaOH}}=\dfrac{0,2}{0,1}=2M\)