tham khảo 

a.b.c.\(n_{Zn}=\dfrac{m}{M}=\dfrac{13}{65}=0,2mol\)

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

0,2                     0,2        0,2  ( mol )

\(m_{ZnCl_2}=n.M=0,2.136=27,2g\)

\(V_{H_2}=n.22,4=0,2.22,4=4,48l\)

d.\(n_{CuO}=\dfrac{m}{M}=\dfrac{32}{80}=0,4mol\)

\(CuO+H_2\rightarrow\left(t^o\right)Cu+H_2O\)

0,4   >  0,2                                 ( mol )

 0,2       0,2            0,2                   ( mol )

\(m_{chất.rắn}=m_{CuO\left(dư\right)}+m_{Cu}=0,2.80+0,2.64=16+12,8=28,8g\)

\(\%m_{CuO}=\dfrac{16}{28,8}.100=55,55\%\)

\(\%m_{Cu}=100\%-55,55\%=44,45\%\)

\(a,PTHH:Zn+2HCl\rightarrow ZnCl_2+H_2\\ Áp.dụng.ĐLBTKL,ta.có:\\ m_{Zn}+m_{HCl}=m_{ZnCl_2}+m_{H_2}\\ m_{H_2}=m_{Zn}+m_{HCl}-m_{ZnCl_2}=6,5+7,3-13,6=0,2\left(g\right)\)

a) PTHH: \(Zn+2HCl\rightarrow ZnCl_2+H_2\uparrow\)

b) Ta có: \(n_{HCl}=2n_{Zn}=2\cdot\dfrac{3,25}{65}=0,1\left(mol\right)\) \(\Rightarrow V_{HCl}=\dfrac{0,1}{0,5}=0,2\left(l\right)\)

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

                   a_________________________\(\dfrac{3}{2}\)a    (mol)

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

                    a____________________a      (mol)

Ta có: \(n_{H_2}=0,05\left(mol\right)=\dfrac{3}{2}a+a\) \(\Rightarrow a=0,02\)

\(\Rightarrow\left\{{}\begin{matrix}\%m_{Al}=\dfrac{0,02\cdot27}{0,02\cdot27+0,02\cdot56}\cdot100\%\approx32,53\%\\\%m_{Fe}=67,47\%\end{matrix}\right.\)

\(n_{HCl}=0,25.2=0,5\left(mol\right)\\ a,PTHH:Zn+2HCl\rightarrow ZnCl_2+H_2\\ b,n_{Zn}=n_{H_2}=n_{ZnCl_2}=\dfrac{0,5}{2}=0,25\left(mol\right)\\ m_{Zn}=0,25.65=16,25\left(g\right)\\ c,V_{H_2\left(đktc\right)}=0,25.22,4=5,6\left(l\right)\)

Không biết đúng không nữa;-;;;

a) PTHH: Zn + 2HCl -> ZnCl2 + H2 

b) HCl=250ml=0,25l

n2HCl= V/22,4= 0,5/22,4= 0,02(mol)

Zn  +  2HCl -> ZnCl2  +  H2

1          2              1         1

0,01 <-0,5--------------> 0,01

mZn= n.M= 0,01.65= 0,65(gam)

c) VH2=n . 22,4= 0,01 . 22,4= 0,224(l)
 

\(n_{Zn}=\dfrac{13}{65}=0,2(mol)\\ a,PTHH:Zn+2HCl\to ZnCl_2+H_2\\ b,n_{HCl}=2n_{Zn}=0,4(mol)\\ \Rightarrow m_{HCl}=0,4.36,5=14,6(g)\\ c,n_{H_2}=n_{Zn}=0,2(mol)\\ \Rightarrow V_{H_2}=0,2.22,4=4,48(l)\)

b) mHCl = 14,6 (g)

V H2 = 4,48 (l)

Giải thích các bước:

a) PTHH:  Zn +  2HCl → ZnCl2 + H2↑

b) nZn = 13 : 65 = 0,2 mol

Theo PTHH: nHCl = 2.nZn = 0,4 mol

mHCl = 0,4 . 36,5 = 14,6(g)

c) nH2 = nZn = 0,2 mol

VH2 = 0,2 . 22,4 = 4,48 (l)

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

Tỉ lệ số nguyên tử Zn : số phân tử HCl : số phân tử ZnCl₂ : số phân tử H₂ = 1 : 2 : 1 : 1 

Bảo toàn khối lượng : 

\(m_{Zn}+m_{HCl}=m_{ZnCl_2}+m_{H_2}\)

\(m_{H_2}=13+14.6-27.2=0.4\left(g\right)\)

- Zn + 2HCl --> ZnCl₂ + H₂

- Tỉ lệ Zn : HCl : ZnCl₂ : H₂ = 1:2:1:1

- Theo ĐLBTKL: \(m_{Zn}+m_{HCl}=m_{ZnCl_2}+m_{H_2}\)

=> \(m_{H_2}=13+14,6-27,2=0,4\left(g\right)\)

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

b. Theo ĐLBTKL, ta có:

\(m_{Zn}+m_{HCl}=m_{ZnCl_2}+m_{H_2}\\ b.\Leftrightarrow6,5+7,3=13,6+m_{H_2}\\ \Leftrightarrow m_{H_2}=\left(6,5+7,3\right)-13,6=0,2\left(g\right)\)

Chúc em học tốt!

\(a,PTHH:Zn+2HCl\to ZnCl_2+H_2\\ b,\text {Bảo toàn KL: }m_{Zn}+m_{HCl}=m_{ZnCl_2}+m_{H_2}\\ \Rightarrow m_{ZnCl_2}=6,5+7,3-0,2=13,6(g)\)