\(n_{H_2}=\dfrac{2,24}{22,4}=0,1(mol)\\ a,Zn+2HCl\to ZnCl_2+H_2\\ b,n_{ZnCl_2}=0,1(mol)\\ \Rightarrow m_{ZnCl_2}=0,1.136=13,6(g)\\ c,n_{Zn}=0,1(mol)\\ \Rightarrow \%_{Zn}=\dfrac{0,1.65}{20}.100\%=32,5\%\\ \Rightarrow \%_{Ag}=100\%-32,5\%=67,5\%\)

áp dụng công thức là ra

Theo bài ra, ta có: \(m_{Ag}=5,6\left(g\right)\)

PTHH: \(2Al+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+3H_2\uparrow\)

a) Ta có: \(n_{H_2}=\dfrac{2,24}{22,4}=0,1\left(mol\right)\) \(\Rightarrow n_{Al}=\dfrac{1}{15}\left(mol\right)\) \(\Rightarrow m_{Al}=\dfrac{1}{15}\cdot27=1,8\left(g\right)\)

\(\Rightarrow\%m_{Al}=\dfrac{1,8}{1,8+5,6}\cdot100\%\approx24,32\%\) \(\Rightarrow\%m_{Ag}=75,68\%\)

b) Theo PTHH: \(n_{H_2SO_4}=n_{H_2}=0,1mol\) \(\Rightarrow C_{M_{H_2SO_4}}=\dfrac{0,1}{0,1}=1\left(M\right)\)

c) PTHH: \(H_2SO_4+Ba\left(OH\right)_2\rightarrow BaSO_4\downarrow+2H_2O\)

Theo PTHH: \(n_{Ba\left(OH\right)_2}=n_{H_2SO_4}=0,1mol\)

\(\Rightarrow V_{ddBa\left(OH\right)_2}=\dfrac{0,1}{0,2}=0,5\left(l\right)=500\left(ml\right)\)

a) Đặt: nZn=x(mol); nFe= y(mol) (x,y: nguyên, dương)

Zn + H2SO4 -> ZnSO4 + H2

x_______x_______x________x

Fe + H2SO4 -> FeSO4 + H2

y____y_________y___y(mol)

b) m(rắn)=mCu=3(g)

=> m(Zn, Fe)= 21,6 - 3= 18,6(g)

Ta có hpt:

\(\left\{{}\begin{matrix}65x+56y=18,6\\22,4x+22,4y=6,72\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=0,2\\y=0,1\end{matrix}\right.\)

=> Zn= 65.0,2=13(g)

=>%mZn= (13/21,6).100=60,185%

%mCu=(3/21,6).100=13,889%

=>%mFe=25,926%

c) nH2SO4=x+y=0,3(mol) =>mH2SO4=29,4(g)

=> mddH2SO4= (29,4.100)/25=117,6(g)

a) $Zn + 2CH_3COOH \to (CH_3COO)_2Zn + H_2$

b) Theo PTHH : 

$n_{Zn} = n_{H_2} = \dfrac{2,24}{22,4} = 0,1(mol)$

$\Rightarrow m_{Cu} = 10,5 - 0,1.65 = 4(gam)$

Cau 1 : 

\(n_{H2}=\dfrac{2,24}{22,4}=0,1\left(mol\right)\)

Pt : \(Fe+2HCl\rightarrow FeCl_2+H_2|\)

        1          2             1         1 

       0,1                                 0,1

a) Chat trong dung dich A thu duoc la : sat (II) clorua

    Chat ran B la : dong

    Chat khi C la : khi hidro

b) \(n_{Fe}=\dfrac{0,1.1}{1}=0,1\left(mol\right)\)

\(m_{Fe}=0,1.56=5,6\left(g\right)\)

\(m_{Cu}=10-5,6=4,4\left(g\right)\)

⁰/₀Fe = \(\dfrac{5,6.100}{10}=56\)⁰/₀

⁰/₀Cu = \(\dfrac{4,4.100}{10}=44\)⁰/₀

c) Co : \(m_{Cu}=4,4\left(g\right)\)

\(n_{Cu}=\dfrac{4,4}{64}=0,06875\left(mol\right)\)

Pt : \(Cu+2H_2SO_{4dac}\underrightarrow{t^o}CuSO_4+SO_2+2H_2O|\)

        1           2                  1              1          2

     0,06875                                    0,06875

\(n_{SO2}=\dfrac{0,06875.1}{1}=0,06875\left(mol\right)\)

\(V_{SO2\left(dktc\right)}=1,54\left(l\right)\)

 Chuc ban hoc tot