\(n_{Mg}=\dfrac{7,2}{24}=0,3\left(mol\right)\\ a,PTHH:Mg+2HCl\rightarrow MgCl_2+H_2\\ b,Theo.PTHH:n_{H_2}=n_{Mg}=0,3\left(mol\right)\\ \Rightarrow V_{H_2\left(đktc\right)}=0,3\cdot22,4=6,72\left(l\right)\)

Ta có sau p/ứ muối tạo thành là \(MgCl_2\)

Do đó \(m=m_{MgCl_2}=0,3\cdot95=28,5\left(g\right)\)

\(n_{Fe}=\dfrac{11.2}{56}=0.2\left(mol\right)\)

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

\(0.2.......0.2......................0.2\)

\(V_{H_2}=0.2\cdot22.4=4.48\left(l\right)\)

\(C\%H_2SO_4=\dfrac{0.2\cdot98\cdot100\%}{200}=9.8\%\)

\(n_{Mg}=\dfrac{2.4}{24}=0.1\left(mol\right)\)

\(Mg+2HCl\rightarrow MgCl_2+H_2\)

\(0.1.......0.2...........0.1........0.1\)

\(m_{dd_{HCl}}=\dfrac{0.2\cdot36.5\cdot100}{14.6}=50\left(g\right)\)

\(V_{H_2}=0.1\cdot22.4=2.24\left(l\right)\)

\(m_{MgCl_2}=0.1\cdot95=9.5\left(g\right)\)

\(m_{\text{dung dịch sau phản ứng}}=2.4+50-0.1\cdot2=52.2\left(g\right)\)

\(C\%_{MgCl_2}=\dfrac{9.5}{52.2}\cdot100\%=18.2\%\)

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

a.

\(CuO+2HCl\rightarrow CuCl_2+H_2O\)

\(Mg+2HCl\rightarrow MgCl_2+H_2\)

b.

\(n_{Mg}=n_{H_2}=0,1\left(mol\right)\Rightarrow m_{Mg}=0,1.24=2,4\left(g\right),m_{CuO}=12-2,4=9,6\left(g\right)\)

c. 

\(m_{muối}=m_{CuCl_2}+m_{MgCl_2}=0,12.135+95.0,1=25,7\left(g\right)\)

a) Zn + 2HCl →ZnCl₂  + H₂

b) nZn = 6,5/65 = 0,1 mol . Theo tỉ lệ pư => nH₂ = nZn = nZnCl₂ =0,1 mol <=> V_H2(đktc) = 0,1.22,4 = 2,24 lít.

c) mZnCl₂ = 0,1 . 136 = 13,6 gam

d) nHCl =2nZn = 0,2 mol => mHCl = 0,2.36,5= 7,3 gam

Cách 2: áp dụng định luật BTKL => mHCl = mZnCl₂ + mH₂ - mZn 

<=> mHCl = 13,6 + 0,1.2 - 6,5 = 7,3 gam

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

PTHH: Zn + 2HCl → ZnCl₂ + H₂

Mol:    0,1                  0,1           0,1

b,\(m_{ZnCl_2}=0,1.136=13,6\left(g\right)\)

c,\(V_{H_2}=0,1.22,4=2,24\left(l\right)\)

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

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

\(n_{ZnCl_2}=n_{Zn}=0,1\left(mol\right)\)

\(\Rightarrow m_{ZnCl_2}=n.M=0,1.136=13,6\left(g\right)\)

c) \(n_{H_2}=n_{Zn}=0,1\left(mol\right)\)

\(V_{H_2}=n.22,4=0,1.22,4=2,24\left(l\right)\)

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

a) Pt : \(Zn+2HCl\rightarrow ZnCl_2+H_2|\)

            1         2              1          1

          0,1                        0,1      0,1

b) \(n_{ZnCl2}=\dfrac{0,1.}{1}=0,1\left(mol\right)\)

⇒ \(m_{ZnCl2}=01,.136=13,6\left(g\right)\)

c) \(n_{H2}=\dfrac{0,1.}{1}=0,1\left(mol\right)\)

\(V_{H2\left(dktc\right)}=01,.22,4=2,24\left(l\right)\)

 Chúc bạn học tốt

ddHCl có C% là bao nhiêu :)?

Câu 9 : 

\(n_{Mg}=\dfrac{4,8}{24}=0,2\left(mol\right)\)

a) Pt : \(Mg+2CH_3COOH\rightarrow\left(CH_3COO\right)_2Mg+H_2\)

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

→ \(V_{H2\left(dtkc\right)}=0,2.22,4=4,48\left(l\right)\)

b) \(V_{ddCH3COOH}=\dfrac{0,4}{2}=0,2\left(l\right)\)

c) \(m_{\left(CH3COO\right)2Mg}=0,2.101=20,2\left(g\right)\)

d) Pt : \(CH_3COOH+KOH\rightarrow CH_3COOK+H_2O\)

                0,4                0,4

\(C_{MddKOH}=\dfrac{0,4}{0,2}=2\left(M\right)\)

 Chúc bạn học tốt

a) 

PTHH: Mg + 2HCl --> MgCl₂ + H₂

       0,075<--0,15--->0,075-->0,075

=> m = 0,075.24 = 1,8 (g)

b) V_H2 = 0,075.22,4 = 1,68 (l)

c) m_MgCl2 = 0,075.95 = 7,125 (g)

d) 

PTHH: 2H₂ + O₂ --t^o--> 2H₂O

           0,075->0,0375

=> V_O2 = 0,0375.22,4 = 0,84 (l)

a.b.c.

\(Mg+2HCl\rightarrow MgCl_2+H_2\)

0,075 0,15           0,075    0,075 ( mol )

\(m_{Mg}=0,075.24=1,8g\)

\(V_{H_2}=0,075.22,4=1,68l\)

\(m_{MgCl_2}=0,075.95=7,125g\)

d.\(2H_2+O_2\rightarrow\left(t^o\right)2H_2O\)

 0,075   0,0375                      ( mol )

\(V_{O_2}=0,0375.22,4=0,84l\)