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

a) \(Fe+H_2SO_4\rightarrow FeSO_4+H_2\)

  \(Al_2O_3+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+3H_2O\)

b) \(n_{Fe}=n_{H2}=n_{H2SO4}=0,1\left(mol\right)\Rightarrow m_{Fe}=0,1.56=5,6\left(g\right)\)

\(\Rightarrow m_{Al2O3}=15,8-5,6=10,2\left(g\right)\)

c) Ta có : \(n_{Al2O3}=\dfrac{10,2}{102}=0,1\left(mol\right)\Rightarrow n_{H2SO4}=3n_{Al2O3}=0,3\left(mol\right)\)

\(C_{MddH2SO4}=\dfrac{0,1+0,3}{0,2}=2M\)

Đáp án D.

Do H₂ chỉ khử được Fe₂O₃ thành Fe nên B gồm Fe và Al₂O₃, chỉ có Fe tạo H₂

\(n_{H_2}=\dfrac{2.24}{22.4}=0.1\left(mol\right)\)

\(Zn+2HCl\rightarrow ZnCl_2+H_2\)

\(0.1.......0.2......................0.1\)

Chất rắn X : Cu 

\(m_{Zn}=0.1\cdot65=6.5\left(g\right)\Rightarrow m_{Cu}=19.3-6.5=12.8\left(g\right)\)

\(n_{Cu}=\dfrac{12.8}{64}=0.2\left(mol\right)\)

\(C_{M_{HCl}}=\dfrac{0.2}{0.2}=1\left(M\right)\)

\(2Cu+O_2\underrightarrow{^{^{t^o}}}2CuO\)

\(0.2........0.1\)

\(m_{tăng}=m_{O_2}=0.1\cdot32=3.2\left(g\right)\)

Ta có: \(n_{H_2}=\dfrac{2,24}{22,4}=0,1\left(mol\right)\)

PT: \(Fe+2HCl\rightarrow FeCl_2+H_2\)

Theo PT: \(n_{HCl}=2n_{H_2}=0,2\left(mol\right)\Rightarrow C_{M_{HCl}}=\dfrac{0,2}{0,1}=2\left(M\right)\)

\(n_{Fe}=n_{H_2}=0,1\left(mol\right)\Rightarrow m_{Fe}=0,1.56=5,6\left(g\right)\)

\(\Rightarrow m_{Cu}=20-5,6=14,4\left(g\right)\)

\(\Rightarrow\left\{{}\begin{matrix}\%m_{Fe}=\dfrac{5,6}{20}.100\%=28\%\\\%m_{Cu}=72\%\end{matrix}\right.\)

a, \(Zn+H_2SO_4\rightarrow ZnSO_4+H_2\)

b, Ta có: \(n_{H_2}=\dfrac{2,24}{22,4}=0,1\left(mol\right)\)

Theo PT: \(n_{Zn}=n_{H_2}=0,1\left(mol\right)\)

\(\Rightarrow\left\{{}\begin{matrix}\%m_{Zn}=\dfrac{0,1.65}{10,5}.100\%\approx61,9\%\\\%m_{Cu}\approx38,1\%\end{matrix}\right.\)

c, \(n_{H_2SO_4}=n_{H_2}=0,1\left(mol\right)\)

\(\Rightarrow C_{M_{H_2SO_4}}=\dfrac{0,1}{0,5}=0,2\left(M\right)\)

\(n_{H_2}=\dfrac{2,24}{22,4}=0,1mol\\ a.Zn+H_2SO_4\rightarrow ZnSO_4+H_2\\ b.n_{Zn}=n_{H_2SO_4}=n_{H_2}=0,1mol\\ m_{Zn}=0,1.65=6,5g\\ \%m_{Zn}=\dfrac{6,5}{10,5}\cdot100\%=61,9\%\\ \%m_{Cu}=100\%-61,9=38,1\%\\ c.C_{M_{H_2SO_4}}=\dfrac{0,1}{0,5}=0,2M\)

a, Mg + 2HCl \(\rightarrow\) MgCl₂ + H₂             Cu + 2HCl \(\rightarrow\) CuCl₂ + H₂

b, \(\left\{{}\begin{matrix}n_{Mg}=x\\n_{Cu}=y\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}24x+64y=16\\x+y=\dfrac{2,24}{22,4}\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}x=-0,24\\y=0,34\end{matrix}\right.\)

Xem lại đầu bài nha

a, \(Zn+2CH_3COOH\rightarrow\left(CH_3COO\right)_2Zn+H_2\)

\(ZnO+2CH_3COOH\rightarrow\left(CH_3COO\right)_2Zn+H_2O\)

b, Ta có: \(n_{H_2}=\dfrac{2,24}{22,4}=0,1\left(mol\right)\)

Theo PT: \(n_{Zn}=n_{H_2}=0,1\left(mol\right)\)

\(\Rightarrow\left\{{}\begin{matrix}\%m_{Zn}=\dfrac{0,1.65}{14,6}.100\%\approx44,52\%\\\%m_{ZnO}\approx55,48\%\end{matrix}\right.\)

c, Ta có: \(n_{ZnO}=\dfrac{14,6-0,1.65}{81}=0,1\left(mol\right)\)

Theo PT: \(n_{CH_3COOH}=2n_{Zn}+2n_{ZnO}=0,4\left(mol\right)\)

PT: \(C_2H_5OH+O_2\underrightarrow{^{mengiam}}CH_3COOH+H_2O\)

Theo PT: \(n_{C_2H_5OH\left(LT\right)}=n_{CH_3COOH}=0,4\left(mol\right)\)

Mà: H = 80%

\(\Rightarrow n_{C_2H_5OH\left(TT\right)}=\dfrac{0,4}{80\%}=0,5\left(mol\right)\)

\(\Rightarrow m_{C_2H_5OH\left(TT\right)}=0,5.46=23\left(g\right)\)

\(\Rightarrow V_{C_2H_5OH}=\dfrac{23}{0,8}=28,75\left(ml\right)\)

\(\Rightarrow V_{C_2H_5OH\left(18,4^o\right)}=\dfrac{28,75}{18,4}.100=156,25\left(ml\right)=0,15625\left(l\right)\)

\(a,PTHH:Zn+2HCl\to ZnCl_2+H_2\\ ZnO+2HCl\to ZnCl_2+H_2O\\ b,n_{H_2}=\dfrac{3,36}{22,4}=0,15(mol)\\ \Rightarrow n_{Zn}=0,15(mol)\Rightarrow m_{Zn}=0,15.65=9,75(g)\\ \Rightarrow \%_{Zn}=\dfrac{9,75}{25,95}.100\%=37,57\%\\ \Rightarrow \%_{ZnO}=(100-37,57)\%=62,43\%\\ c,n_{ZnO}=\dfrac{25,95-9,75}{81}=0,2(mol)\\ \Rightarrow n_{HCl}=2.0,15+2.0,2=0,7(mol)\\ \Rightarrow m_{dd_{HCl}}=\dfrac{0,7.36,5}{12\%}=212,92(g)\)