Bài tập 14 :

a, PTHH : \(2Cu+O_2\rightarrow2CuO\)

\(n_{Cu}=\frac{m_{Cu}}{M_{Cu}}=\frac{6,4}{64}=0,1\left(mol\right)\)

- Theo PTHH : \(n_{CuO}=n_{Cu}=0,1\left(mol\right)\)

-> \(m_{CuO}=n_{CuO}.M_{CuO}=0,1.\left(64+16\right)=8\left(g\right)\)

a) PTHH: Cu + 1/2 O2 -to-> CuO

nCu= 6,4/64= 0,1(mol) => nCuO= nCu= 0,1(mol)

=> mCuO= 0,1. 80=8(g)

b) PTHH: Cu + 1/2 O2 -to-> CuO

nCu= 12,8/64= 0,2(mol)

nO2= 6,72/22,4= 0,3(mol)

Vì: 0,2/1 < 0,3/1 => O2 dư, Cu hết, tính theo nCu

=> nCuO= nCu= 0,2(mol)

=> mCuO= 0,2.80=16(g)

a) PT: Cu + 1/2 O2 -to-> CuO

nCu= 6,4/64= 0,1(mol) => nCuO= nCu= 0,1(mol)

=> mCuO= 0,1. 80=8(g)

b) PT: Cu + 1/2 O2 -to-> CuO

nCu= 12,8/64= 0,2(mol)

nO2= 6,72/22,4= 0,3(mol)

Vì: 0,2/1 < 0,3/1

=> O2 dư, Cu hết

=> nCuO= nCu= 0,2(mol)

=> mCuO= 0,2.80=16(g)

10.

\(n_{Fe}=\dfrac{16.8}{56}=0.3\left(mol\right)\)

\(4Fe+3O_2\underrightarrow{^{^{t^0}}}2Fe_2O_3\)

\(0.3.....0.225....0.15\)

\(V_{O_2}=0.225\cdot22.4=5.04\left(l\right)\)

\(Fe_2O_3+3H_2SO_4\rightarrow Fe_2\left(SO_4\right)_3+3H_2O\)

\(0.15...........0.45\)

\(m_{H_2SO_4}=0.45\cdot98=44.1\left(g\right)\)

11.

\(n_{Fe_2O_3}=\dfrac{48}{160}=0.3\left(mol\right)\)

\(Fe_2O_3+6HCl\rightarrow2FeCl_3+3H_2O\)

\(0.3...........1.8...........0.6\)

\(m_{FeCl_3}=0.6\cdot162.5=97.5\left(g\right)\)

\(m_{HCl}=1.8\cdot36.5=65.7\left(g\right)\)

Bài 10:

\(a,n_{Fe}=\dfrac{16,8}{56}=0,3(mol)\\ PTHH:4Fe+3O_2\xrightarrow{t^o}2Fe_2O_3\\ Fe_2O_3+3H_2SO_4\to Fe_2(SO_4)_3+3H_2O\\ \Rightarrow n_{O_2}=\dfrac{3}{4}n_{Fe}=0,225(mol)\\ \Rightarrow V_{O_2}=0,225.22,4=5,04(l)\\ b,n_{H_2SO_4}=3n_{Fe_2O_3}=3.\dfrac{1}{2}n_{Fe}=0,45(mol)\\ \Rightarrow m_{H_2SO_4}=0,45.98=44,1(g)\)

Bài 11:

\(a,n_{Fe_2O_3}=\dfrac{48}{160}=0,3(mol)\\ PTHH:Fe_2O_3+6HCl\to 2FeCl_3+3H_2O\\ \Rightarrow n_{FeCl_3}=2n_{Fe_2O_3}=0,6(mol)\\ \Rightarrow m_{FeCl_3}=0,6.162,5=97,5(g)\\ b,n_{HCl}=6n_{Fe_2O_3}=1,8(mol)\\ \Rightarrow m_{HCl}=1,8.36,5=65,7(g)\)

lỗi ảnh ?

2KMnO4-to>K2MnO2+MnO2+O2

2--------------------------------------1 mol

n KMnO4= 31,6\158=2 mol

=>VO2=1.22,4=22,4l

2Cu+O2-to>2CuO

          1----------2 mol

=>m CuO=2.80=160g

Theo ĐLBTKL

\(m_{Cu}+m_{O_2}=m_{CuO}\\ =>m_{CuO}=12,8+3,2=16\left(g\right)\)

\(a/n_{Fe}=\dfrac{16,8}{56}=0,3mol\\ 4Fe+3O_2\xrightarrow[]{t^0}2Fe_2O_3\\ n_{O_2}=\dfrac{0,3.3}{4}=0,225mol\\ V_{O_2,đktc}=0,225.22,4=5,04l\\ V_{O_2,đkc}=0,225.24,79=5,57775l\\ b/n_{Fe_2O_3}=\dfrac{0,3.2}{4}=0,15mol\\ m_{Fe_2O_3}=0,15.160=24g\)

a) PTHH: \(4Fe+3O_2\underrightarrow{t^o}2Fe_2O_3\) 

Ta có: \(n_{Fe}=\dfrac{m}{M}=\dfrac{16,8}{56}=0,3\left(mol\right)\)

PTPƯ: 4Fe         +         3O₂          \(\underrightarrow{t^o}\)          2Fe₂O₃

             4                         3                              2

            0,3                    0,225                         0,15

\(\Rightarrow V_{O_2}=n.24,79=0,225.24,79=5,57775\left(l\right)\) 

TT:mFe=16.8g

a/Tìm VO2?

b/Tìm mH2SO4?

Giải:a/ 

PTHH: t° 

nFe=mFe/M=16.8/56=0,3mol

Theo PTHH:4molFe-->3molO2 

0,3molFe-->nO2=0,3molFe.3/4=0,225mol

4molFE-->2molFe2O3

0,3molFe-->nFe2O3=0,3molFe.2/4=0,15mol

VO2=nO2.22,4=0,225.22,4=5,04l

b/PTHH:Fe2O3+3H2SO4->Fe2(SO4)3+3H2O

Theo PTHH:1molFe2O3-->3molH2SO4

0,15molFe2O3-->nH2SO4=0,15.3/1=0,45mol

mH2SO4=nH2SO4.M

               =0,45.(2+32+16.4)

               =44,1g

Giải vậy đc chưa bạn:)

Em tách từng câu hỏi gồm 1 hoặc 2 bài nhé ! Đăng nhiều như thế này rối lắm.

a)

\(2Cu + O_2 \xrightarrow{t^o} 2CuO\)

b)

\(n_{Cu} = \dfrac{16,8}{64} = 0,2625(mol)\)

2Cu        +      O₂          \(\xrightarrow{t^o}\)       2CuO

0,2625........0,13125................0,2625.......................(mol)

Vậy :

\(m_{O_2} = 0,13125.32 = 4,2(gam)\\ m_{CuO} = 0,2625.80 = 21(gam)\)

c)

2KMnO₄ \(\xrightarrow{t^o}\) K₂MnO₄ + MnO₂ + O₂

0,2625.......................................0,13125................(mol)

\(m_{KMnO_4} = 0,2625.158 = 41,475(gam)\)