K
Khách

Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.

a)\( Fe+2HCl\rightarrow FeCl_2+H_2\\Zn+2HCl\rightarrow ZmCl_2+H_2\\ n_{H_2}=\dfrac{11,2}{22,4}=0,5\left(mol\right)\)

Gọi a là số \(mol\) \(Fe\), b là số \(mol\) \(Zn\)

\(56a+65b=29,8\\ a+b=0,5\\ \Rightarrow a=0,3;b=0,2\\ \%m_{Fe}=\dfrac{0,3.56}{29,8.100\%}=56,38\%\\ \%m_{Zn}=00-56,8=43.62\%\) 

b)\(n_{HCl}=0,5\times2=1\left(mol\right)\\ C_{M_{HCl}}=\dfrac{1}{0,6}=\dfrac{5}{3}M\) 

c)Chịuuuu

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

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

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:

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

 

24 tháng 2 2018

nH2 = 0,5 mol

Đặt nFe = x

nZn = y

Fe + 2HCl → FeCl2 + H2 (1)

x......2x...........x.............x

Zn + 2HCl → ZnCl2 + H2 (2)

y........2y..............y........y

Từ (1)(2) ta có hệ

\(\left\{{}\begin{matrix}56x+65y=29,8\\x+y=0,5\end{matrix}\right.\)

\(\left\{{}\begin{matrix}x=0,3\\y=0,2\end{matrix}\right.\)

⇒ %Fe = \(\dfrac{0,3.56.100\%}{29,8}\)\(\approx\)56,38%

⇒ %Zn = \(\dfrac{0,2.65.100\%}{29,8}\)\(\approx\) 43,62%

⇒ CM HCl = \(\dfrac{1}{0,6}\) = \(\dfrac{5}{3}\) (M)

6 tháng 12 2021

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

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

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

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

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

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

PTHH: \(Fe+2HCl\rightarrow FeCl_2+H_2\uparrow\)

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

\(\Rightarrow\left\{{}\begin{matrix}n_{HCl}=0,2\left(mol\right)\\\%m_{Fe}=\dfrac{0,1\cdot56}{12}\cdot100\%\approx46,67\%\end{matrix}\right.\) \(\Rightarrow\left\{{}\begin{matrix}C_{M_{HCl}}=\dfrac{0,2}{0,2}=1\left(M\right)\\\%m_{Cu}=53,33\%\end{matrix}\right.\)

9 tháng 12 2021

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

Cu không phản ứng

\(nH_2=nFe=\dfrac{2,24}{22,4}=0,1mol\)

\(\rightarrow mFe=0,1.56=5,6gam\)

\(\rightarrow\%mFe=\dfrac{5,6}{12}.100\%=46,\left(6\right)\%\)

\(\rightarrow\%mCu=100\%-46,\left(6\right)\%=53,\left(3\right)\%\)

c)

\(CM_{HCl}=\dfrac{0,1.2}{0,2}=1M\)

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

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

10 tháng 4 2022

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

\(n_{H_2}=\dfrac{15,68}{22,4}=0,7\left(mol\right)\\ m_{HCl}=200.27,375\%=54,75\left(g\right)\\ n_{HCl}=\dfrac{54,75}{36,5}=1,5\left(mol\right)\)

PTHH:

Zn + 2HCl ---> ZnCl2 + H2

a ----> 2a --------> a -----> a

Fe + 2HCl ---> FeCl2 + H2

b ---> 2b -------> b ------> b

Hệ pt \(\left\{{}\begin{matrix}65a+56b=43,7\\a+b=0,7\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}a=0,5\left(mol\right)\\b=0,2\left(mol\right)\end{matrix}\right.\)

\(\rightarrow\left\{{}\begin{matrix}m_{Zn}=0,5.65=32,5\left(g\right)\\m_{Fe}=0,2.56=11,2\left(g\right)\end{matrix}\right.\)

\(m_{dd}=43,7+200-0,7.2=242,3\left(g\right)\\ \rightarrow\left\{{}\begin{matrix}C\%_{ZnCl_2}=\dfrac{0,5.136}{242,3}=28,06\%\\C\%_{FeCl_2}=\dfrac{0,2.127}{242,3}=10,48\%\\C\%_{HCl\left(dư\right)}=\dfrac{\left(1,5-0,5.2-0,2.2\right).36,5}{242,3}=1,51\%\end{matrix}\right.\)

 

10 tháng 4 2022

\(n_{H_2}=\dfrac{15,68}{22,4}=0,7\left(mol\right)\\ pthh:\left\{{}\begin{matrix}Zn+H_2SO_4->ZnSO_4+H_2\\Fe+H_2SO_4->FeSO_{\text{ 4 }}+H_2\end{matrix}\right.\)
 gọi số mol Zn là x , số mol Fe là y 
=> 65x+56y=43,7
=> a+b=0,7 
=>a=0,5 , b =0,2  
=> \(m_{Zn}=0,5.65=32,5\\ m_{Fe}=43,7-32,5=11,2\left(G\right)\)
 

25 tháng 11 2016

2Al + 2H2O + 2NaOH→ 3H2 + 2NaAlO2

0,2mol 0,3mol

mAl=0,2.27=5,4g

2Al + 6HCl→ 2AlCl3+ 3H2

0,2mol 0,3mol

Fe + 2HCl→ FeCl2+ H2

0,15mol 0,45-0,3 mol

mFe=0,15.56=8,4g

mCu=32,8-(6,4+8,4)=18g

%mFe=\(\frac{8,4}{32,8}.100=25,6\%\)

%mCu=\(\frac{18}{32,8}.100=54,8\%\)

%mAl=19,6%

7 tháng 9 2021

nH2=0,5(mol)

Mg+2HCl−−>MgCl2+H2↑

x..........2x.........................x..............x

Fe+2HCl−−>FeCl2+H2↑

y........2y....................y....................y

{24x+56y=20x+y=0,5⇒{x=0,25y=0,25

7 tháng 9 2021

Phần a nữa ạ