Ta có:

\\(\\%m_{Fe2O3}=60\\%.20=12\\left(g\\right)\\Rightarrow n_{Fe2O3}=\\frac{12}{160}=0,075\\left(mol\\right)\\)

\\(\\%m_{CuO}=40\\%.20=8\\left(g\\right)\\Rightarrow n_{CuO}=\\frac{8}{80}=0,1\\left(mol\\right)\\)

\\(Fe_2O_3+3H_2\\rightarrow2Fe+3H_2O\\)

_0,075__________0,15_____

\\(CuO+H_2\\rightarrow Cu+H_2O\\)

_0,1___________0,1_____

\\(\\left\\{{}\\begin{matrix}m_{Fe}=0,15.56=8,4\\left(g\\right)\\\\m_{Cu}=0,1.64=6,4\\left(g\\right)\\end{matrix}\\right.\\)

\\(\\Rightarrow\\left\\{{}\\begin{matrix}\\%m_{Fe}=\\frac{8,4}{8,4+6,4}.100\\%=56,76\\%\\\\\\%m_{Cu}=100\\%-56,76\\%=43,24\\%\\end{matrix}\\right.\\)

hỗn hợp 100% <=> 20g 
1. fe2o3 60% <=> 12g <=> 0,075mol 
cuo 40% <=> 8g <=> 0,1 mol 
Ta có: 
Fe2O3 + 3H2 --> 2Fe + 3H2O 
mol: 0,075 0,225 0,15 
CuO + H2 → Cu + H20 
mol: 0.1 0.1 0.1 
mFe= 0,15x56=8,4g. mCu=0,1x64= 6,4g 
nH2= 0,225+0,1=0,325mol ==> V H2 = 0,325x 22,4 = 7,28 lít 

Tk

nH2O = 12,6/18 = 0,7 (mol)

PTHH: 

CuO + H2 -> (t°) Cu + H2O

Fe2O3 + 3H2 -> (t°) 2Fe + 3H2O

Từ PTHH: nH2 = nH2O = 0,7 (mol)

mH2 = 0,7 . 2 = 1,4 (g)

Áp dụng ĐLBTKL, ta có:

moxit + mH2 = mkl + mH2O

=> moxit = 36,8 + 12,6 - 1,4 = 48 (g)

=> B

\(Fe_2O_3+3H_2\rightarrow\left(t^o\right)2Fe+3H_2O\\ CuO+H_2\rightarrow\left(t^o\right)Cu+H_2O\\ Đặt:n_{Fe_2O_3}=a\left(mol\right);n_{CuO}=b\left(mol\right)\left(a,b>0\right)\\ m_{hhoxit}=k\left(g\right)\\ \Rightarrow\left(1\right)160a+80b=k\\ \left(2\right)112a+64b=0,72k\\ \Rightarrow6,4a=12,8b\\ \Leftrightarrow\dfrac{a}{b}=\dfrac{12,8}{6,4}=\dfrac{2}{1}\\ \Rightarrow\%m_{Fe_2O_3}=\dfrac{160.2}{160.2+80.1}.100=80\%\\ \Rightarrow\%m_{CuO}=20\%\)

PT: \(Fe_2O_3+3H_2\underrightarrow{t^o}2Fe+3H_2O\)

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

a, Ta có: \(\left\{{}\begin{matrix}m_{Fe_2O_3}=20.60\%=12\left(g\right)\Rightarrow n_{Fe_2O_3}=\dfrac{12}{160}=0,075\left(mol\right)\\m_{CuO}=20-12=8\left(g\right)\Rightarrow n_{CuO}=\dfrac{8}{80}=0,1\left(mol\right)\end{matrix}\right.\)

Theo pT: \(\left\{{}\begin{matrix}n_{Fe}=2n_{Fe_2O_3}=0,15\left(mol\right)\\n_{Cu}=n_{CuO}=0,1\left(mol\right)\end{matrix}\right.\)

\(\Rightarrow m_{Fe}=0,15.56=8,4\left(g\right)\)

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

b, Theo PT: \(n_{H_2}=3n_{Fe_2O_3}+n_{CuO}=0,325\left(mol\right)\)

\(\Rightarrow V_{H_2}=0,325.22,4=7,28\left(l\right)\)

Bạn tham khảo nhé!

1)

Phần trăm O trong oxit là 100% -76% = 24%

$CO + O_{oxit} \to CO_2$

Ta thấy : 

m khí tăng = m O(oxit) = 9,6(gam)

=> m1 = 9,6/24% = 40(gam)

n O(oxit) = 9,6/16 = 0,6(mol)

Bảo toàn khối lượng : 

m kim loại = m oxit - m O = 40 - 0,6.16 = 30,4(gam)

$Fe + 2HCl \to FeCl_2 + H_2$
n Fe = n H2 = 4,48/22,4 = 0,2(mol)

=> m Cu = m 2 = 30,4 - 0,2.56 = 19,2(gam)

b)

n CuO = n Cu = 19,2/64 = 0,3(mol)

Ta có : 

n O(trong oxit sắt) = n O(oxit) - n O(trong CuO) = 0,6 -0,3 = 0,3(mol)

Ta thấy : 

n Fe : n O = 0,2 : 0,3 = 2 : 3

Vậy oxit cần tìm là Fe2O3