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30 tháng 12 2021

a, \(n_{H_2}=0,25\left(mol\right)\)

Bảo toàn e:

\(2n_{Zn}=2n_{H_2}\Rightarrow n_{Zn}=0,25\left(mol\right)\)

\(\Rightarrow m_{Zn}=16,25\left(g\right)\)

\(\Rightarrow m_{Cu}=13,75\left(g\right)\)

30 tháng 12 2021

b, \(\%m_{Cu}=\dfrac{13,75}{30}=45,83\%\)

\(\Rightarrow\%m_{Zn}=100\%-45,83\%=54,17\%\)

4 tháng 4 2020

a,

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

\(n_{H2}=\frac{5,6}{22,4}=0,25\left(mol\right)\)

\(n_{Zn}=n_{H2}=0,25\left(mol\right)\)

\(m_{Zn}=0,25.65=16,25\left(g\right)\)

\(m_{Cu}=30-16,25=13,75\left(g\right)\)

b)

\(\%m_{Zn}=\frac{16,25}{30}.100\%=54,17\%\)

\(\%m_{Cu}=100\%-54,17\%=45,83\%\)

c)

\(n_{HCl}=2n_{H2}=0,5\left(mol\right)\)

\(\Rightarrow CM_{HCl}=\frac{0,5.36,5}{200}.100\%=9,125\%\)

4 tháng 1 2023

a, PT: \(Fe+2HCl\rightarrow FeCl_2+H_2\)

Ta có: \(n_{H_2}=\dfrac{5,6}{22,4}=0,25\left(mol\right)\)

Theo PT: \(n_{Fe}=n_{H_2}=0,25\left(mol\right)\)

\(\Rightarrow m_{Fe}=0,25.56=14\left(g\right)\)

mCu = 20,4 - 14 = 6,4 (g)

b, \(\left\{{}\begin{matrix}\%m_{Fe}=\dfrac{14}{20,4}.100\%\approx68,63\%\\\%m_{Cu}\approx31,37\%\end{matrix}\right.\)

c, Theo PT: \(n_{HCl}=2n_{H_2}=0,5\left(mol\right)\)

\(\Rightarrow C\%_{HCl}=\dfrac{0,5.36,5}{200}.100\%=9,125\%\)

6 tháng 12 2021

\(Fe+2HCl\rightarrow FeCl_2+H_2\)

\(n_{Fe}=n_{H_2}=\dfrac{3.36}{22.4}=0.15\left(mol\right)\)

\(\Rightarrow m_{Fe}=0.15\cdot56=8.4\left(g\right)\)

\(m_{Cu}=m_{hh}-m_{Fe}=15-8.4=6.6\left(g\right)\)

\(n_{HCl}=2n_{H_2}=0.15\cdot2=0.3\left(mol\right)\)

\(C_{M_{HCl}}=\dfrac{0.3}{0.2}=1.5\left(M\right)\)

26 tháng 3 2022

Gọi \(\left\{{}\begin{matrix}n_{Ag}=a\left(mol\right)\\n_{FeO}=b\left(mol\right)\end{matrix}\right.\)

\(n_{SO_2}=\dfrac{1,344}{22,4}=0,6\left(mol\right)\)

PTHH:

\(2Ag+2H_2SO_4\rightarrow Ag_2SO_4+SO_2\uparrow+2H_2O\)

a             a                \(\dfrac{a}{2}\)             \(\dfrac{a}{2}\)

\(2FeO+4H_2SO_4\rightarrow Fe_2\left(SO_4\right)_3+SO_2\uparrow+4H_2O\)

b                 2b               \(\dfrac{b}{2}\)                \(\dfrac{b}{2}\)

Hệ pt

\(\left\{{}\begin{matrix}108a+72b=11,52\\\dfrac{a}{2}+\dfrac{b}{2}=0,06\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}a=0,08\left(mol\right)\\b=0,04\left(mol\right)\end{matrix}\right.\\ \Rightarrow\left\{{}\begin{matrix}m_{Ag}=0,08.108=8,64\left(g\right)\\m_{FeO}=0,04.72=2,88\left(g\right)\end{matrix}\right.\\ \Rightarrow\left\{{}\begin{matrix}\%m_{Ag}=\dfrac{8,64}{11,52}=75\%\\\%m_{FeO}=100\%-75\%=25\%\end{matrix}\right.\)

b, \(\rightarrow n_{H_2SO_4}=0,08+0,4.2=0,16\left(mol\right)\\ \rightarrow C_{MddH_2SO_4}=\dfrac{0,16}{0,8}=0,2M\)

c, \(n_{NaOH}=1,25.0,5=0,625\left(mol\right)\)

PTHH:

\(6NaOH+Fe_2\left(SO_4\right)_3\rightarrow2Fe\left(OH\right)_3+3Na_2SO_4\)

LTL: \(\dfrac{0,625}{6}>\dfrac{0,04}{2}\) => NaOH dư

Theo pthh:

\(\left\{{}\begin{matrix}n_{NaOH\left(pư\right)}=6n_{Fe_2\left(SO_4\right)_3}=6.0,04=0,24\left(mol\right)\\n_{Na_2SO_4}=3n_{Fe_2\left(SO_4\right)_3}=3.0,04=0,12\left(mol\right)\end{matrix}\right.\\ \Rightarrow\left\{{}\begin{matrix}C_{MddNaOH\left(dư\right)}=\dfrac{0,24}{0,5}=0,48M\\C_{MddNa_2SO_4}=\dfrac{0,12}{0,5}=0,24M\end{matrix}\right.\)

 

12 tháng 2 2020

1.

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

\(n_{H2}=\frac{5,6}{22,4}=0,25\left(mol\right)\)

\(n_{Zn}=n_{H2}=0,25\left(mol\right)\)

\(\rightarrow,m_{Zn}=0,25.65=16,25\left(g\right);m_{Cu}=30-16,25=13,75\left(g\right)\)

b)

\(\%m_{Zn}=\frac{16,25}{30}.100\%=54,17\%\)

\(\%m_{Cu}=100\%-54,17\%=45,83\%\)

c)

\(n_{HCl}=2n_{H2}=0,5\left(mol\right)\)

\(C\%_{HCl}=\frac{0,5.36,5}{200}.100\%=9,125\%\)

2.

a)

\(Fe+2HCl\rightarrow FeCl_2+H_2\)

\(n_{H2}=\frac{3,36}{22,4}=0,15\left(mol\right)\)\(m_{Fe}=0,15.65=8,4\left(g\right),m_{Ag}=15-8,4=6,6\left(g\right)\)

b)

\(\%m_{Fe}=\frac{8,4}{15}.100\%=56\%\)

\(\%m_{Ag}=100\%-56\%=44\%\)

c)

\(n_{HCl}=2n_{H2}=0,3\left(mol\right)\)

\(\rightarrow m_{dd_{HCL}}=\frac{0,3.36,5}{15,6\%}=70,19\left(g\right)\)

21 tháng 3 2023

a, \(Zn+2HCl\rightarrow ZnCl_2+H_2\)

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

Theo PT: \(n_{Zn}=n_{H_2}=1\left(mol\right)\Rightarrow m_{Zn}=1.65=65\left(g\right)\)

\(\Rightarrow m_{Cu}=80,5-65=15,5\left(g\right)\)