Zn+2Hcl->ZnCl2+H2

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

n Zn=0,2 mol

=>VH2 =0,2.22,4=4,48l

mZncl2=0,2.136=27,2g

3H2+Fe2O3-to>2Fe+3H2O

0,2---------------------2\15 

->m Fe=2\15.56=7,467g

nZn= 13/65=0,2(mol)

a) PTHH: Zn +  2 HCl -> ZnCl2 + H2

b) nH2=nZnCl2=nZn=0,2(mol)

=>V(H2,đktc)=0,2 x 22,4= 4,48(l)

c) khối lượng muối sau phản ứng chứ nhỉ? 

mZnCl2=136.0,2=27,2(g)

.

_ \(m_{Fe_2O_3}=0,8.50=40\left(g\right)\) \(\Rightarrow m_{CuO}=50-40=10\left(g\right)\)

_ \(n_{Fe_2O_3}=\dfrac{40}{160}=0,25mol\); \(n_{CuO}=\dfrac{10}{80}=0,125mol\)

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

_____0,75mol_0,25mol

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

0,125__0,125 (mol)

\(\Rightarrow V_{H_2}=\left(0,75+0,125\right)22,4=19,6l\)

1.

\(M_{CuO}\)= 64 + 16 = 80 (g)

\(M_{Fe_2O_3}\)= 56 .2+16.3 = 160 (g)

Theo đề bài cho:

\(m_{Fe_2O_3}=\frac{80}{100}\times50=40\left(g\right)\)

\(\rightarrow n_{Fe_2O_3}=\frac{40}{160}=0,25\left(mol\right)\)

\(m_{CuO}=\frac{20}{100}\times50=10\left(g\right)\)

\(\rightarrow n_{CuO}=\frac{10}{80}=0,125\left(mol\right)\)

Phương trình hóa học:

\(CuO+H_2\rightarrow Cu+H_2O\) (1)

0,125mol - 0,125 mol

\(Fe_2O_3+3H_2\rightarrow2Fe+3H_2O\) (2)

0,25mol- 0,75 mol

\(\Sigma n_{khí}H_2\)cần dùng: 0,125 + 0,75=0,875 mol

\(\Rightarrow V_{H_2}=0,875\times22,4=19,6l\)

Fe₂O₃+3H₂-to>2Fe+3H₂O

0,05-----0,15------0,1

CuO+H₂-to>Cu+H₂O

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

ta có CuOchiếm 33,3%

=> m _CuO=12.\(\dfrac{33,3}{100}\)= 4g

=>n _CuO=\(\dfrac{4}{80}\)=0,05 mol

=>m _Fe2O3=12-4=8g

->n _Fe2O3=\(\dfrac{8}{160}\)=0,05 mol

=>V_H2= 0,2.22,4=4,48l

=>m Y=0,1.56+0,05.64=8,8g

Bài 1 : 

$FeO + H_2 \xrightarrow{t^o} Fe + H_2O$
$CuO + H_2 \xrightarrow{t^o} Cu + H_2O$

Theo PTHH :

$n_{Fe} = n_{FeO} = \dfrac{1,44}{72} = 0,02(mol)$
$n_{Cu} = n_{CuO} = \dfrac{4}{80} = 0,05(mol)$
$m_{kim\ loại} = 0,02.56 + 0,05.64 = 4,32(gam)$

Bài 2 : 

Gọi $n_{Mg} = a(mol) ; n_{Al} = b(mol)$
$\Rightarrow 24a + 27b = 7,8(1)$
$2Mg + O_2 \xrightarrow{t^o} 2MgO$

$4Al + 3O_2 \xrightarrow{t^o} 2Al_2O_3$

Theo PTHH :

$n_{MgO} = n_{Mg} =a (mol)$
$n_{Al_2O_3} = 0,5n_{Al} = 0,5b(mol)$
$\Rightarrow 40a + 0,5b.102 = 14,2(2)$

Từ (1)(2) suy ra a = 0,1 ; b = 0,2

$\%m_{Mg} = \dfrac{0,1.24}{7,8}.100\% = 3,08\%$

$\%m_{Al} = 100\% -3,08\% = 96,92\%$

CuO+H2= Cu+H2O

Fe2O3+3H2=2Fe+3H2O

mFe2O3=\(\frac{50.20}{100}\)= 10g

nfe2o3= 10:56=0,18 mol

mcuo= 50-10=40 g

ncuo= 40:(64+16)=0,5 mol

theo pthh

nh2=3nfe2o3=0,54 mol

nh2=ncuo=0,5 mol

=>tông số mol h2= 0,5+0,54=1,04 mol

vh2=1,04.22,4=23,296 mol

các loại pư trên thuộc loại pư thế

mFe2O3=80%.50=40(g)

=>nFe2O3=40/160=0,25(mol)

mCuO=50-40=10(g)

=>nCuO=10/80=0,125(mol)

Fe2O3+3H2--t*-->2Fe+3H2O

0,75____0,75

CuO+H2--t*-->Cu+H2O

0,125__0,125

\(\Sigma H_2=\)0,75+0,125=0,875(mol)

=>VH2=0,875.22,4=19,6(l)

\(m_{CuO}=40.20\%=8\left(g\right)\)

\(n_{CuO}=\dfrac{8}{80}=0,1\left(mol\right)\)

\(n_{Fe_2O_3}=\dfrac{40-8}{160}=0,2\left(mol\right)\)

PTHH:

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

 0,1      0,1

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

0,2          0,6 

\(V_{H_2}=\left(0,1+0,6\right).22,4=15,68\left(l\right)\)