a)\(n_{Cu}=\dfrac{3,2}{64}=0,05\left(m\right)\)

\(PTHH:2Cu+O_2\underrightarrow{t^O}2CuO\)

tỉ lệ       : 2         1       2

số mol  :0,05    0,025  0,05

\(m_{CuO}=0,05.80=4\left(g\right)\)

b)\(V_{O_2}=0,025.22,4=0,56\left(l\right)\)

\(V_{kk}=\dfrac{0,56}{20\%}=2,8\left(l\right)\)

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

\(PTHH:CuO+H_2\xrightarrow[]{}Cu+H_2O\)

tỉ lệ        :1          1         1       1

số mlo   :0,1       0,1       0,1     0,1

\(m_{Cu}=0,1.64=6,4\left(g\right)\)

\(n_{Fe}=\dfrac{1,68}{56}=0,03\left(mol\right)\)

\(3Fe+2O_2\rightarrow\left(t^o\right)Fe_3O_4\)

 0,03   0,02               0,01  ( mol )

\(m_{Fe_3O_4}=0,01.232=2,32\left(g\right)\)

\(V_{kk}=0,02.22,4.5=2,24\left(l\right)\)

\(2KClO_3\rightarrow\left(t^o\right)2KCl+3O_2\)

   \(\dfrac{1}{75}\)                               0,02   ( mol )

\(m_{KClO_3}=\dfrac{1}{75}.122,5=1,63\left(g\right)\)

a,nFe=1,68/56=0,03 mol

Ta có PTHH : 3Fe + 2O2 --> Fe3O4 (1) ( ở trên dấu --> có to nha )

Theo PTHH ta có :

nFe3O4=1/3nFe=1/3.0,03=0,01 mol

nO2=2/3nFe=2/3.0,03=0,02 mol

=>mFe3O4= 0,01.232=2,32g

=>Vkk=5.(0,02.22,4)=2,24 l

b, Ta có PTHH: 2KClO3 --> 2KCl + 3O2 (2) ( trên dấu --> vẫn có to )

Gọi x là số mol KClO3 cần dùng ( x > 0 )

Theo PTHH (3) và theo bài ra ta có PTHH sau:

2/3x=0,02 

=> x=0,03 mol

=> mKClO3= 0,03.122,5= 3,675g

\(n_{CuO}=2a\left(mol\right)\Rightarrow n_{Fe_2O_3}=a\left(mol\right)\)

\(m_X=80\cdot2a+160a=80\left(g\right)\)

\(\Rightarrow a=0.25\left(mol\right)\)

\(CuO+H_2\underrightarrow{^{^{t^0}}}Cu+H_2O\)

\(Fe_2O_3+3H_2\underrightarrow{^{^{t^0}}}2Fe+3H_2O\)

\(n_{H_2}=0.5+0.25\cdot3=1.25\left(mol\right)\)

\(V_{H_2}=1.25\cdot22.4=28\left(l\right)\)

\(m_{cr}=0.5\cdot64+0.5\cdot56=60\left(g\right)\)

\(n_{CuO}=\dfrac{m}{M}=\dfrac{12}{64+16}=0,15\left(mol\right)\)

\(a,PTHH:CuO+H_2\underrightarrow{t^o}Cu+H_2O\)

                  \(0,15:0,15:0,15\left(mol\right)\)

\(b,m_{Cu}=n.M=0,15.64=9,6\left(g\right)\)

\(c,V_{H_2}=n.22,4=0,15.22,4=3,36\left(l\right)\)

a) nFe = 16,8/56 = 0,3 (mol)

PTHH: 3Fe + 2O2 -> (t°) Fe3O4

Mol: 0,3 ---> 0,2 ---> 0,1

mFe3O4 = 0,1 . 232 = 23,2 (g)

b) VO2 = 0,2 . 22,4 = 4,48 (l)

Vkk = 4,48 . 5 = 22,4 (l)

c) H = 100% - 20% = 80%

nO2 (LT) = 0,2 : 80% = 0,25 (mol)

PTHH: 2KMnO4 -> (t°) K2MnO4 + MnO2 + O2

nKMnO4 = 0,25 . 2 = 0,5 (mol)

mKMnO4 = 0,5 . 158 = 79 (g)

a.b.\(n_{Fe_2O_3}=\dfrac{8}{160}=0,05\left(mol\right)\)

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

\(Fe_2O_3+3H_2\rightarrow\left(t^o\right)2Fe+3H_2O\)

0,05  >    0,1                                  ( mol )

\(\dfrac{1}{30}\)          0,1               \(\dfrac{1}{15}\)                  ( mol )

\(m_{thu.được}=m_{Fe_2O_3\left(dư\right)}+m_{Fe}\)

               \(=\left(0,05-\dfrac{1}{30}\right).160+\dfrac{1}{15}.56=6,4\left(g\right)\)

c. Để khử hết oxit sắt thì thể tích H₂ cần dùng

\(Fe_2O_3+3H_2\rightarrow\left(t^o\right)2Fe+3H_2O\)

 0,05         0,15                          ( mol )

\(V_{H_2}=0,15.22,4=3,36\left(l\right)\)

Ta có: \(n_{O_2}=\dfrac{8,96}{22,4}=0,4\left(mol\right)\)

PT: \(2Mg+O_2\underrightarrow{t^o}2MgO\)

___0,8____0,4__0,8 (mol)

a, \(m_{Mg}=0,8.24=19,2\left(g\right)\)

b, \(m_{MgO}=0,8.40=32\left(g\right)\)

Bạn tham khảo nhé!

\(a) CuO + H_2 \xrightarrow{t^o} Cu + H_2O\\ n_{Cu} = n_{H_2} = n_{CuO} = \dfrac{8}{80} = 0,1(mol)\\ m_{Cu} = 0,1.64 = 6,4(gam)\\ b) V_{H_2} = 0,1.22,4 = 2,24(lít)\)