Gọi \(n_{Fe}=x\left(mol\right)\)\(;n_{Zn}=y\left(mol\right)\)

\(n_{H_2}=\dfrac{6,72}{22,4}=0,3mol\)

Ta có:  \(\left\{{}\begin{matrix}56x+65y=18,6\\2x+2y=2n_{H_2}=0,6\end{matrix}\right.\)\(\Rightarrow\left\{{}\begin{matrix}x=0,1\\y=0,2\end{matrix}\right.\)

\(\%m_{Fe}=\dfrac{0,1\cdot56}{18,6}\cdot100\%=30,11\%\)

\(\%m_{Zn}=100\%-30,11\%=69,89\%\)

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

0,1     0,2

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

0,2     0,4

\(n_{HCl}=0,2+0,4=0,6mol\)

\(C_M=\dfrac{n}{V}=\dfrac{0,6}{0,2}=3M\)

\(a)n_{Fe}=\dfrac{5,6}{56}=0,1mol\\ Fe+2HCl\rightarrow FeCl_2+H_2\)

0,1       0,2            0,1          0,1

\(m_{FeCl_2}=0,1.127=12,7g\\ b)V_{H_2}=0,1.22,4=2,24l\\ c)C_{M_{HCl}}=\dfrac{0,2}{0,2}=1M\)

\(n_{Zn}=\dfrac{19,5}{65}=0,3\left(mol\right)\\ PTHH:Zn+2HCl\rightarrow ZnCl_2+H_2\uparrow\)

(mol).......0,3........0,6.........0,3.......0,3

a) \(V_{H_2}=0,3.22,4=6,72\left(l\right)\)

b) \(m_{ZnCl_2}=0,3.136=40,8\left(g\right)\)

c) \(200ml=0,2l\)

\(C_{M_{HCl}}=\dfrac{0,6}{0,2}=3\left(M\right)\)

d) \(n_{CuO}=\dfrac{16}{80}=0,2\left(mol\right)\)

\(PTHH:CuO+H_2\underrightarrow{t^o}Cu+H_2O\)

Ban đầu: 0,2......0,3

Phản ứng: 0,2....0,2.....0,2.....0,2

Dư:.....................0,1

Lập tỉ lệ: \(\dfrac{0,2}{1}< \dfrac{0,3}{1}\left(0,2< 0,3\right)\)

\(\Rightarrow H_2\) dư

\(a)n_{Fe}=\dfrac{25,2}{56}=0,45mol\\ Fe+2HCl\rightarrow FeCl_2+H_2\)

0,45       0,9          0,45       0,45

\(V_{H_2\left(đktc\right)}=0,45.22,4=10,08l\\ b)C_{M\left(HCl\right)}=\dfrac{0,9}{0,2}=4,5M\\ c)C_{M\left(FeCl_2\right)}=\dfrac{0,45}{0,2}=2,25M\)

Fe + 2HCl -> FeCl2 + H2
nFe = 5,6/56 = 0,1 mol
=>nH2 = 0,1 mol
=> VH2= 0,1*22,4= 2,24 lít

\(n_{Fe}=\dfrac{5,6}{56}=0,1\left(mol\right)\)

PTHH: Fe + 2HCl ---> FeCl₂ + H₂

          0,1-->0,2------------------>0,1

=> \(\left\{{}\begin{matrix}m_{ddHCl}=\dfrac{0,2.36,5}{15\%}=\dfrac{146}{3}\left(g\right)\\V_{H_2}=0,1.22,4=4,48\left(l\right)\end{matrix}\right.\)

a, \(Mg+2HCl\rightarrow MgCl_2+H_2\)

b, \(m_{Mg}=\dfrac{7,2}{24}=0,3\left(mol\right)\)

Theo PT: \(n_{MgCl_2}=n_{Mg}=0,3\left(mol\right)\Rightarrow m_{MgCl_2}=0,3.95=28,5\left(g\right)\)

c, \(n_{HCl}=2n_{Mg}=0,6\left(mol\right)\)

\(\Rightarrow C_{M_{HCl}}=\dfrac{0,6}{0,2}=3\left(M\right)\)

mình đang cần gấp

;-;tui cũng đang thắc mắc câu này

Theo đề bài ta có : nH2 = 10,08/22,4 = 0,45 (mol)

a) PTHH :

0,45mol->,9mol->0,45mol

b) khối lượng mạt sắt tham gia phản ứng là :

mFe = 0,45.56 = 25,2(g)

c)

nồng độ mol của dd HCl đã dùng là :

CMddHCl = 0,9/0,15 = 6(M)

a)

$Fe + H_2SO_4 \to FeSO_4 + H_2$

Theo PTHH : 

$n_{Fe} = n_{H_2} = \dfrac{3,36}{22,4} = 0,15(mol)$
$m_{Fe} = 0,15.56 = 8,4(gam)$

b)

$n_{H_2SO_4} = n_{H_2} = 0,15(mol)$
$C_{M_{H_2SO_4}} = \dfrac{0,15}{0,05} = 3M$

c)

$n_{FeSO_4} = n_{H_2} = 0,15(mol)$
$C_{M_{FeSO_4}} = \dfrac{0,15}{0,05} = 3M$