Ta có: \(n_{Fe}=\dfrac{28}{56}=0,5\left(mol\right)\)

a, PT: \(Fe+H_2SO_4\rightarrow FeSO_4+H_2\)

______0,5____0,5_____0,5_____0,5 (mol)

b, m_H2SO4 = 0,5.98 = 49 (g)

c, m_FeSO4 = 0,5.152 = 76 (g)

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

____0,5__0,5 (mol)

⇒ m_Cu = 0,5.64 = 32 (g)

Bạn tham khảo nhé!

a) \(n_{SO_3}=\dfrac{m}{M}=\dfrac{32}{80}=0,4\left(mol\right)\)

PTHH: `SO_3 + H_2O -> H_2SO_4`

b) Theo PTHH: `n_{H_2SO_4} = n_{SO_3} = 0,4 (mol)`

`=> m_{H_2SO_4} = 0,4.98 = 39,2 (g)`

2Al + 3H2SO4 -----> Al2(SO4)3 + 3H2

nAl = 7,1/27 = 71/270 ( mol)

=> nH2 = 71/180 ( mol)

=> VH2= 8,86 lit

=> m muối=71\540 .342=44,967g

\(n_{Al}=\dfrac{7,1}{27}=\dfrac{71}{270}\left(mol\right)\\ pthh:2Al+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+3H_2\) 
            \(\dfrac{71}{270}\)                      \(\dfrac{71}{540}\)          \(\dfrac{71}{180}\) 
\(V_{H_2}=\dfrac{71}{540}.22,4=3l\\ m_{Al_2\left(SO_4\right)_3}=342.\dfrac{71}{180}=134,9g\)

a2Al+3H2SO4(dung dịch pha loãng)->Al2(SO4)3+3H2↑

b, nAl= 7,1/27=0,2 mol

Theo PTHH ta có: nH2=3/2 nAl= 3/2 . 0,2 = 0,3 mol

=> VH2(dktc)= 0,3 . 22,4= 6,72 lít

c, nAl2SO4= 1/2 . nAl= 1/2 . 0,2=0,1 mol

=> mAl2SO4=nAL2SO4+ MAl2SO4= 0,1 .  150 =15 g

\(\left(a\right)2Al+3H_2O\rightarrow Al_2\left(SO_4\right)_3+3H_2\\ \left(b\right)n_{H_2}=\dfrac{13,44}{22,4}=0,6mol\\ n_{Al}=\dfrac{0,6.2}{3}=0,4mol\\ m_{Al}=0,4.27=10,8g\\ \left(c\right)n_{O_2}=\dfrac{4,8}{32}=0,15mol\\ 4Al+3O_2\underrightarrow{t^0}2Al_2O_3\\ \Rightarrow\dfrac{0,4}{4}>\dfrac{0,15}{3}\Rightarrow Al.dư\\ n_{Al_2O_3}=\dfrac{0,15.2}{3}=0,1mol\\ m_{oxit}=m_{Al_2O_3}=0,1.102=10,2g\)

a: \(2Al+3H_2SO_4\rightarrow1Al_2\left(SO_4\right)_3+3H_2\uparrow\)

    0,4           0,6                0,2             0,6

b: \(n_{H_2}=\dfrac{13.44}{22.4}=0.6\left(mol\right)\)

=>\(n_{Al}=0.4\left(mol\right)\)

\(m_{Al}=0.4\cdot27=10.8\left(g\right)\)

c: \(4Al+3O_2\rightarrow2Al_2O_3\)

0,4                      0,2

\(m_{Al_2O_3}=0.2\left(27\cdot2+16\cdot3\right)=0.2\cdot102=20.4\left(g\right)\)

\(n_{H_2}=\dfrac{13,44}{22,4}=0,6\left(mol\right)\)

PTHH ;

2Al + 3H2SO4 --> Al2(SO4)3 + 3H2↑

  0,4           0,6               0,2           0,6

4Al + 3O2 ---> 2Al2O3

0,2       0,15          0,1 

\(n_{O_2}=\dfrac{4,8}{32}=0,15\left(mol\right)\)

\(\dfrac{0,4}{4}>\dfrac{0,15}{3}\)

--> Tính theo oxi

\(b,m_{Al}=0,4.27=10,8\left(g\right)\)

\(c,m_{Al_2O_3}=0,1.102=10,2\left(g\right)\)

a) \(Mg+H_2SO_4\rightarrow MgSO_4+H_2\)

\(2Al+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+3H_2\)

b) \(n_{H_2\left(1\right)}=n_{Mg}=\dfrac{4,8}{24}=0,2\left(mol\right)\)

\(n_{H_2\left(2\right)}=\dfrac{3}{2}n_{Al}=\dfrac{3}{2}.\dfrac{2,7}{27}=0,15\left(mol\right)\)

=> \(V=\left(0,2+0,15\right).22,4=7,84\left(l\right)\)

c) \(n_{H_2SO_4\left(1\right)}=n_{Mg}=0,2\left(mol\right)\)

\(n_{H_2SO_4\left(2\right)}=\dfrac{3}{2}n_{Al}=0,15\left(mol\right)\)

=> \(m_{ddH_2SO_4}=\dfrac{0,35.98}{20\%}=171,5\left(g\right)\)

d) \(m_{ddsaupu}=4,8+2,7+171,5-0,35.2=178,3\left(g\right)\)

\(C\%_{MgSO_4}=\dfrac{120.0,1}{178,3}.100=6,73\%\)

\(C\%_{Al_2\left(SO_4\right)_3}=\dfrac{342.0,05}{178,3}.100=9,59\%\)

a,Mg+H2SO4-> MgSO4 +H2

2Al +3H2SO4 -> Al2(SO4)3 +3H2

b, n(Mg)=0,2mol

n(Al)=0,1mol

Số mol H2SO4=số mol H2= 0,2+ 0,1*3/2 =0,35mol

V(H2)= 7,84lit

c, MgSO4: m=0,2*120=24(g)

Al2(SO4)3 : m=342*0,05= 17,1(g)

d, khối lượng H2SO4= 0,35*98=34,3(g)

Khối lượng dd H2SO4 là: 

m(dd)=34,3*100/20 = 171,5(g)

e,khối lượng dd sau pứ 

m= m(Mg) +m(Al) + m(dd H2SO4) -m(H2) = 4,8+2,7+171,5-0,35*2=178,3(g)

C%(MgSO4)= 24*100%/178,3 =13,46%

C%(Al2SO4)3 = 17,1*100%/178,3 =9,59%

Câu 4 : 

Vì bạc không tác dụng với axit sunfuric loãng : 

\(n_{H2}=\dfrac{0,224}{22,4}=0,01\left(mol\right)\)

a) Pt : \(Zn+H_2SO_4\rightarrow ZnSO_4+H_2|\) 

             1           1                1           1

             0,01                       0,01      0,01

b) \(n_{Zn}=\dfrac{0,0.1}{1}=0,01\left(mol\right)\)

\(m_{Zn}=0,01.65=0,65\left(g\right)\)

\(m_{Ag}=1,73-0,65=1,08\left(g\right)\)

⁰/₀Zn = \(\dfrac{0,65.100}{1,73}=37,57\)⁰/₀

⁰/₀Ag = \(\dfrac{1,08.100}{1,73}=62,43\)⁰/₀

c) \(n_{ZnSO4}=\dfrac{0,01.1}{1}=0,01\left(mol\right)\)

⇒ \(m_{ZnSO4}=0,01.161=1,61\left(g\right)\)

 Chúc bạn học tốt

\(nMg=\dfrac{12}{24}=0,5\left(mol\right)\)

\(nH_2SO_4=\dfrac{29,4}{98}=0,3\left(mol\right)\)

\(Mg+H_2SO_4\rightarrow MgSO_4+H_2\)

  1         1                 1            1     (mol)

 0,3        0,3          0,3           0,3     (mol)

LTL : 0,5/1  > 0,3/1 

=> Mg dư , H2SO4 đủ

\(VH_2=0,3.22,4=6,72\left(l\right)\)

m muối là mMgSO4

=> \(m\left(muối\right)=mMgSO_4=0,3.120=36\left(g\right)\)

Bài 5:

có thêm đc câu 6 thì tốt. Em cảm ơn ạ