\(n_{Zn}=\dfrac{6,5}{65}=0,1\left(mol\right)\)

\(n_{CuO}=\dfrac{20}{80}=0,25\left(mol\right)\)

PTHH: Zn + 2HCl ---> ZnCl₂ + H₂

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

=> \(\left\{{}\begin{matrix}V_{H_2}=0,1.22,4=2,24\left(l\right)\\C_{M\left(HCl\right)}=\dfrac{0,2}{0,2}=1M\end{matrix}\right.\)

PTHH: CuO + H₂ --t^o--> Cu + H₂O
LTL: 0,25 > 0,1 => CuO dư

Theo pthh: n_Cu = n_H2 = 0,1 (mol)

=> m_Cu = 0,1.64 = 6,4 (g)

\(n_{Zn}=\dfrac{6,5}{65}=0,1\left(mol\right)\\ pthh:Zn+2HCl\rightarrow ZnCl_2+H_2\) 
         0,1    0,2                           0,2 
\(V_{H_2}=0,2.22,4=4,48l\\ C_M=\dfrac{0,2}{0,2}=1M\\ n_{CuO}=\dfrac{20}{80}=0,25\left(G\right)\\ pthh:CuO+H_2\underrightarrow{t^o}Cu+H_2O\\ LTL:0,25>0,1\) 
=>CuO dư 
\(n_{Cu}=n_{H_2}=0,1\left(mol\right)\\ m_{Cu}=0,1.64=6,4g\)

\(n_{H_2SO_4}=1.0,2=0,2(mol)\\ H_2SO_4+BaCl_2\to BaSO_4\downarrow+2HCl\\ \Rightarrow n_{BaSO_4}=n_{BaCl_2}=0,2(mol)\\ a,m_{BaSO_4}=0,2.233=46,6(g)\\ b,V_{dd_{BaCl_2}}=\dfrac{0,2}{1,5}\approx 0,13(l)\\ c,n_{HCl}=0,4(mol)\\ \Rightarrow C_{M_{HCl}}=\dfrac{0,4}{0,2+0,13}\approx 1,21M\)

\(d,\) Dd sau p/ứ là HCl nên làm quỳ tím hóa đỏ

\(n_{H_2SO_4}=0,2.1=0,2\left(mol\right)\\ H_2SO_4+BaCl_2\rightarrow BaSO_4+2HCl\\ n_{BaCl_2}=n_{BaSO_4}=n_{H_2SO_4}=0,2\left(mol\right)\\ n_{HCl}=2.0,2=0,4\left(mol\right)\\ a,m_{\downarrow}=m_{BaSO_4}=0,2.233=46,6\left(g\right)\\ b,V_{\text{dd}BaCl_2}=\dfrac{0,2}{1,5}=\dfrac{2}{15}\left(l\right)\\ c,C_{M\text{dd}HCl}=\dfrac{0,4}{\dfrac{2}{15}+0,2}=1,2\left(M\right)\\ d,V\text{ì}.c\text{ó}.\text{dd}.HCl\Rightarrow Qu\text{ỳ}.ho\text{á}.\text{đ}\text{ỏ}\)

200ml = 0,2l

\(n_{H2SO4}=1.0,2=0,2\left(mol\right)\)

Pt : \(BaCl_2+H_2SO_4\rightarrow BaSO_4+2HCl|\)

           1           1                  1              2

          0,2        0,2               0,2           0,4

a) \(n_{BaSO4}=\dfrac{0,2.1}{1}=0,2\left(mol\right)\)

⇒ \(m_{BaSO4}=0,2.233=46,6\left(g\right)\)

b) \(n_{BaCl2}=\dfrac{0,2.1}{1}=0,2\left(mol\right)\)

\(V_{ddBaCl2}=\dfrac{0,2}{1,5}=\dfrac{2}{15}\left(l\right)=133,33\left(ml\right)\)

c) \(n_{HCl}=\dfrac{0,2.2}{1}=0,4\left(mol\right)\)

\(V_{ddspu}=0,2+\dfrac{2}{15}=\dfrac{1}{3}\left(l\right)\)

\(C_{M_{ddHCl}}=\dfrac{0,4}{\dfrac{1}{3}}=1,2\left(M\right)\)

d) Cho quỳ tím vào dung dịch sau phản ứng , quỳ tím hóa đỏ. Vì dung dịch thu được sau phản ứng có HCl là axit

 Chúc bạn học tốt

a)

Coi V dd HCl = 100(ml)

m dd HCl = 1,25.100 = 125(gam)

n HCl = 125.7,3%/36,5 = 0,25(mol)

[H⁺ ] = [Cl^- ] = CM HCl = 0,25/0,1 = 2,5M

b)

n Al = 0,235(mol)

2Al + 6HCl $\to$ 2AlCl3 + 3H2

n HCl pư = 3n Al = 0,705(mol)

n HCl dư = 0,4.2 - 0,705 = 0,095(mol)

[H⁺ ] = CM HCl dư = 0,095/0,4 = 0,2375M

pH = -log([H⁺ ]) = 0,624

a) \(n_{H_2}=\dfrac{3,36}{22,4}=0,15\left(mol\right)\)

PTHH: R + 2HCl --> RCl₂ + H₂

____0,15<-----------------0,15

=> \(M_R=\dfrac{3,6}{0,15}=24\left(Mg\right)\)

b) 

PTHH: Mg + 2HCl --> MgCl₂ + H₂

__________0,3<-----0,15<---0,15

=> \(V=\dfrac{0,3}{2}=0,15\left(l\right)=150\left(ml\right)\)

\(C_{M\left(MgCl_2\right)}=\dfrac{0,15}{0,15}=1M\)

\(a.n_{H_2}=\dfrac{3,36}{22,4}=0,15\left(mol\right)\\ PTHH:R+2HCl\rightarrow RCl_2+H_2\\ \Rightarrow n_R=n_{H_2}=0,15\left(mol\right)\\ \Rightarrow M_R=\dfrac{m_R}{n_R}=\dfrac{3,6}{0,15}=24\\ \) 

\(\Rightarrow R\) là \(Magie\left(Mg\right)\) 

\(b.n_{HCl}=2.n_{H_2}=2.0,15=0,3\left(mol\right)\\ \Rightarrow V_{ddHCl}=\dfrac{n_{HCl}}{C_M}=\dfrac{0,3}{2}=0,15\left(l\right)=150ml\) 

\(n_{MgCl_2}=n_{Mg}=0,15\left(mol\right)\\ \Rightarrow C_{M_{ddMgCl_2}}=\dfrac{n_{MgCl_2}}{V}=\dfrac{0,15}{0,15}=1\left(M\right)\)

\(n_{Fe}=\dfrac{11,2}{56}=0,2\left(mol\right)\)

a.

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

\(V_{H_2}=24,79.0,2=4,958\left(l\right)\)

b.

\(n_{HCl}=2.n_{Fe}=0,4\left(mol\right)\\ CM_{HCl}=\dfrac{0,4}{0,2}=2M\)