n Al=0,25 mol

2Al + 6HCl → 2AlCl₃ + 3H₂

0,25---0,75------0,25------0,375 mol

=>VH2=0,375.22,4=8,4l

=>m AlCl3=0,25.133,5=33,375g

=>CM HCl=\(\dfrac{0,75}{2}\)=0,375M

2K+2H2O->2KOH+H2

0,1-----0,1-----0,1---0,05

n K=0,1 mol

=>m KOH=0,1.56=5,6g

=>VH2=0,05.22,4=1,12l

2H2+O2-to>2H2O

0,05--------------0,05

n O2=0,2 mol

=>O2 dư

=>mH2O=0,05.18=0,9g

Ba + 2H2O -- > Ba(OH)2 + H2

nBa = 27,4 / 137 = 0,2 (mol)

mBa(OH)2 = 0,2 . 171 = 34,2 (g)

VH2 = 0,2.22,4 = 4,48 (l)

VH2(thực tế ) = 4,48 .80%=3,584  (l ) 

Ba + 2H2O -- > Ba(OH)2 + H2

nBa = 27,4 / 137 = 0,2 (mol)

mBa(OH)2 = 0,2 . 171 = 34,2 (g)

VH2 = 0,2.22,4 = 4,48 (l)

VH2(thực tế ) = 4,48 : 5 = 0,896 (l ) 

nFe = 5.6/56 = 0.1 (mol) 

nHCl = 0.2*2 = 0.4 (mol) 

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

LTL : 0.1/1 < 0.4/2 => HCl dư 

mHCl dư = ( 0.4 - 0.2 ) * 36.5 = 7.3 (g) 

VH2 = 0.2*22.4 = 4.48 (l) 

CM FeCl2 = 0.1/0.2 = 0.5(M)

CM HCl dư = 0.2 / 0.2 = 1(M) 

Ca + 2H2O --> Ca(OH)2 + H2

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

nCa=8/40=0,2(mol)

b/

mCa(OH)2=0,2.74=14,8(g)

VH2=0,2.22,4.80%=3,584(l)

PTHH: \(2K+2H_2O\rightarrow2KOH+H_2\)

\(n_K=\dfrac{7,8}{39}=0,2\left(mol\right)\)

Theo PTHH: \(n_{H_2}=\dfrac{1}{2}n_K=\dfrac{1}{2}.0,2=0,1\left(mol\right)\)

\(2H_2+O_2\xrightarrow[]{t^o}2H_2O\)

Theo PTHH: \(n_{O_2}=\dfrac{1}{2}n_{H_2}=\dfrac{1}{2}.0,1=0,05\left(mol\right)\)

\(\Rightarrow V_{O_2}=n_{O_2}.22.4=0,05.22,4=1,12\left(l\right)\)

Thể tích không khí đã dùng:

\(V_{kk}=\dfrac{V_{O_2}.100\%}{20\%}==5,6\left(l\right)\)

nFe = 11,2/56 = 0,2 (mol)

PTHH: Fe + 2HCl -> FeCl2 + H2

Mol: 0,2 ---> 0,4 ---> 0,2 ---> 0,2

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

PTHH: CuO + H2 -> (to) Cu + H2O

Mol: 0,2 <--- 0,2 ---> 0,2

mCu = 0,2 . 64 = 12,8 (g)

\(a,PTHH:Fe+2HCl\rightarrow FeCl_2+H_2\uparrow\)

\(b,n_{Fe}=\dfrac{m}{M}=\dfrac{11,2}{56}=0,2mol\)

\(\Rightarrow n_{H_2}=0,2mol\Rightarrow V_{H_2}=n.22,4=4,48l\)

\(\Rightarrow n_{FeCl_2}=0,2mol\)

\(c,m_{FeCl_2}=n.M=0,2.92,5=18,5g\)

\(n_{Mg}=\dfrac{4,8}{24}=0,2\left(mol\right)\\ pthh:Mg+2HCl\rightarrow MgCl_2+H_2\) 
          0,2       0,4                      0,2  
\(\Rightarrow m_{HCl}=0,4.36,5=14,6\left(g\right)\\ V_{H_2}=0,2.22,4=4,48\left(l\right)\\ pthh:FeO+H_2\underrightarrow{t^o}Fe+H_2O\) 
           0,2      0,2    0,2
\(m_{Fe}=0,2.56=11,2\left(g\right)\)

a)PTHH: Na+H2O---> NaOH+H2
b)nNa= \(\dfrac{m}{M}=\dfrac{2,3}{23}=0,1\left(mol\right)\)

=>n_Na=n_H2=0,1 (mol)

=>V_H2=n.22,4=0,1.22,4=2,24(l)

c)n_Na=n_H2O=n_NaOH=0,1 (mol)

=>m_H2O=0,1.18=1,8(g)

d)m_NaOH=0,1.(23+16+1)=4(g)

Học tốt !

a, \(2Na+2H_2O\rightarrow2NaOH+H_2\)

b, \(n_{Na}=\dfrac{2,3}{23}=0,1\left(mol\right)\)

Theo PT: \(n_{H_2}=\dfrac{1}{2}n_{Na}=0,05\left(mol\right)\Rightarrow V_{H_2}=0,05.22,4=1,12\left(l\right)\)

c, \(n_{H_2O}=n_{Na}=0,1\left(mol\right)\Rightarrow m_{H_2O}=0,1.18=1,8\left(g\right)\)

d, \(n_{NaOH}=n_{Na}=0,1\left(mol\right)\Rightarrow m_{NaOH}=0,1.40=4\left(g\right)\)