Câu 8 : 

\(n_{MgCO3}=\dfrac{42}{84}=0,5\left(mol\right)\)

Pt : \(2CH_3COOH+MgCO_3\rightarrow\left(CH_3COO\right)_2Mg+CO_2+H_2O\)

                 1                  0,5                                         0,5

a) \(V_{CO2\left(dktc\right)}=0,5.22,4=11,2\left(l\right)\)

b) \(V_{CH3COOH}=\dfrac{1}{2}=0,5\left(l\right)\)

c) Pt : \(CH_3COOH+NaOH\rightarrow CH_3COONa+H_2O\)

                  1                                         1

300ml = 0,3l

\(C_{MCH3COONa}=\dfrac{1}{0,3}=\dfrac{10}{3}\left(M\right)\)

 Chúc bạn học tốt

2Al+6HCl-->2AlCl₃+3H₂

0,3----0,9---------0,3------0,45

=>n _Al=8,1\17=0,3 mol

=>V_H2=0,45.22,4=10,08l

=>m _HCl=0,9.26,5=32,85g

=>m_AlCl3=0,3.133,5=40,05g

C2 :Bảo Toàn khối lượng 

=>m _AlCl3=40,05g

$a)PTHH:2Al+6HCl\to 2AlCl_3+3H_2$

$b)n_{Al}=\dfrac{5,4}{27}=0,2(mol)$

Theo PT: $n_{H_2}=1,5.n_{Al}=0,3(mol)$

$\Rightarrow V_{H_2}=0,3.22,4=6,72(lít)$

$c)$Theo PT: $n_{HCl}=3n_{Al}=0,6(mol)$

$\Rightarrow m_{HCl}=0,6.36,5=21,9(g)$

$d)PTHH:2H_2+O_2\xrightarrow{t^o}2H_2O$

Theo PT: $n_{H_2O}=n_{H_2}=0,3(mol)$

$\Rightarrow m_{H_2O}=0,3.18=5,4(g)$

2Al+6HCl->2AlCl₃+3H₂

0,2--0,6----------------0,3

2H₂+O₂-to>2H₂O

0,3-------------0,3

=>n _Al=\(\dfrac{5,4}{27}\)=0,2 mol

=>V_H2=0,3.22,4=6,72l

=>m _HCl=0,6.26,5=21,9g

=>m _H2O=0,3.18=5,4g

\(a,PTHH:2Al+6HCl\rightarrow2AlCl_3+3H_2\)

\(b,n_{Al}=\dfrac{m}{M}=\dfrac{5,4}{27}=0,2\left(mol\right)\\ Theo.PTHH:n_{H_2}=\dfrac{3}{2}.n_{Al}=\dfrac{3}{2}.0,2=0,3\left(mol\right)\\ V_{H_2\left(đktc\right)}=n.22,4=0,3.22,4=6,72\left(l\right)\)

\(c,Theo.PTHH:n_{HCl}=3.n_{Al}=3.0,2=0,6\left(mol\right)\\ m_{HCl}=n.M=0,6.36,5=21,9\left(g\right)\)

\(d,PTHH:2H_2+O_2\underrightarrow{t^o}2H_2O\\ Theo.PTHH:n_{H_2O}=n_{H_2}=0,3\left(mol\right)\\ m_{H_2O}=n.M=0,3.18=5,4\left(g\right)\)

B nha

a. 2Al + 6HCl -> 2AlCl₃ + 3H₂

b. n_Al = \(\dfrac{8.1}{27}=0,3\left(mol\right)\)=> \(n_{H_2}=\dfrac{3}{2}.0,3=0,45\left(mol\right)\)

\(V_{H_2}=0,45.22,4=10,08\left(mol\right)\)

c. \(n_{HCl}=3n_{Al}=3.0,3=0,9\left(mol\right)=>m_{HCl}=0,9.36,5=32,85\left(g\right)\)

Vậy m = 32,85

BTKL: \(m_{Fe}+m_{HCl}=m_{muối}+m_{H_2}\)

 \(\Rightarrow m_{H_2}=5,6+7,3-12,7=0,2\left(g\right)\)

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

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)

\(SO_3+H_2O\rightarrow H_2SO_4\\ n_{H_2SO_4}=n_{SO_3}=\dfrac{6,72}{22,4}=0,3\left(mol\right)\\ a,m=m_{H_2SO_4}=98.0,3=29,4\left(g\right)\\ b,C\%_{ddH_2SO_4}=\dfrac{29,4}{0,3.80+150}.100\approx16,897\%\\ c,H_2SO_4:Tính.axit\Rightarrow Quỳ.tím.hoá.đỏ\)

\(n_{Fe_2O_3}=\dfrac{16}{160}=0,1\left(mol\right)\\ n_{HCl}=\dfrac{73.10\%}{36,5}=0,2\left(mol\right)\\ Fe_2O_3+6HCl\rightarrow2FeCl_3+3H_2O\\ Vì:\dfrac{0,1}{1}>\dfrac{0,2}{6}\\ \Rightarrow Fe_2O_3dư\\ a.Muối.tạo.thành:FeCl_3\\ n_{FeCl_3}=\dfrac{2}{6}.0,2=\dfrac{1}{15}\left(mol\right)\\ m_{FeCl_3}=\dfrac{1}{15}.162,5=\dfrac{65}{6}\left(g\right)\\ b.Chất.tan.ddA:FeCl_3\\ m_{ddFeCl_3}=m_{Fe_2O_3\left(p.ứ\right)}+m_{ddHCl}=\dfrac{1}{6}.0,2.160+73=\dfrac{235}{3}\left(g\right)\\ C\%_{ddFeCl_3}=\dfrac{\dfrac{65}{6}}{\dfrac{235}{3}}.100=13,83\%\)

\(n_{Mg}=\dfrac{6}{24}=0,25(mol)\\ PTHH:Mg+2HCl\to MgCl_2+H_2\\ a,n_{H_2}=n_{Mg}=0,25(mol)\\ \Rightarrow V_{H_2}=0,25.22,4=5,6(l)\\ b,PTHH:CuO+H_2\xrightarrow{t^o}Cu+H_2O\\ \Rightarrow n_{Cu}=n_{H_2}=0,25(mol)\\ \Rightarrow m_{Cu}=0,25.64=16(g)\)