PT: \(2ZnS+3O_2\underrightarrow{t^o}2ZnO+2SO_2\)

Ta có: \(n_{ZnS}=\dfrac{19,4}{97}=0,2\left(mol\right)\)

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

Xét tỉ lệ: \(\dfrac{0,2}{2}< \dfrac{0,4}{3}\), ta được O₂ dư.

Theo PT: \(n_{SO_2}=n_{ZnS}=0,2\left(mol\right)\)

\(\Rightarrow V_{SO_2}=0,2.22,4=4,48\left(l\right)\)

Bạn tham khảo nhé!

\(n_{ZnS} = \dfrac{19,4}{97} = 0,2(mol)\\ n_{O_2} = \dfrac{8,96}{22,4} = 0,4(mol)\\ 2ZnS + 3O_2 \xrightarrow{t^o} 2ZnO + 2SO_2\\ \dfrac{n_{Zn}}{2} = 0,1 < \dfrac{n_{O_2}}{3} = 0,133\)

Do đó, oxi dư

\(n_{SO_2} = n_{ZnS} = 0,2(mol)\\ \Rightarrow V_{SO_2} = 0,2.22,4 = 4,48(lít)\)

\(a,PTHH:2ZnS+3O_2\underrightarrow{t^O}2ZnO+2SO_2\) 
\(n_{ZnS}=\dfrac{19,4}{97}=0,2\left(mol\right)\\ n_{O_2}=\dfrac{8,96}{22,4}=0,4\left(mol\right)\) 
\(pthh:2ZnS+3O_2\underrightarrow{t^O}2ZnO+2SO_2\) 
LTL:\(\dfrac{0,2}{2}< \dfrac{0,4}{3}\) 
=> O₂ dư  
theo pthh: \(n_{SO_2}=n_{ZnO}=n_{Zn}=0,2\left(mol\right)\) 
\(m_A=m_{ZnO}=0,2.81=16,2\left(g\right)\) 
Khí B gồm 1 nguyên tử S và 2 nguyên tử O 
dB/kk = \(\dfrac{64}{29}\)

\(m_{CH_4}=0,3.16=4,8(g)\)

Bảo toàn KL: \(m_{CH_4}+m_{O_2}=m_{CO_2}+m_{H_2O}\)

\(\Rightarrow m_{O_2}=10,8+13,2-4,8=19,2(g)\\ \Rightarrow V_{O_2}=\dfrac{19,2}{32}.22,4=13,44(l)\\ \Rightarrow V_{kk}=13,44.5=67,2(l)\)

Zn+2HCl->Zncl2+H2

0,4----0,8----0,4----0,4

n Zn=0,4 mol

VH2=0,4.22,4=8,96l

m ZnCl2=0,4.136=54,4g

2H2+O2-to>2H2O

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

n O2=0,2 mol

=>pứ hết 

=>m H2O=0,4.18=7,2g

a.b.\(n_{Zn}=\dfrac{26}{65}=0,4mol\)

\(Zn+2HCl\rightarrow ZnCl_2+H_2\)

0,4                      0,4       0,4       ( mol )

\(m_{ZnCl_2}=0,4.136=54,4g\)

\(V_{H_2}=0,4.22,4=8,96l\)

c.\(n_{O_2}=\dfrac{4,48}{22,4}=0,2mol\)

\(2H_2+O_2\rightarrow\left(t^o\right)2H_2O\)

0,4   = 0,2                       ( mol )

0,4        0,2            0,4        ( mol )

\(m_{H_2O}=0,4.18=7,2g\)

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

Zn + 2HCl  --- > ZnCl2 + H2 

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

mZnCl2 = 0,2 . 136 = 27,2 (g)

VH2 = 0,2 . 22,4 = 4,48(l)

\(n_{Zn}=\dfrac{m}{M}=\dfrac{13}{65}=0,2mol\)

\(PTHH:Zn+2HCl\rightarrow ZnCl+H_2\uparrow\)

               \(1\)    :    \(2\)     :     \(1\)    :    \(1\)    \(\left(mol\right)\)

              \(0,2\)       \(0,4\)       \(0,2\)       \(0,2\)   \(\left(mol\right)\)

\(b,m_{ZnCl_2}=n.M=0,2.136=27,2\left(g\right)\)

\(c,V_{H_2}=n.22,4=0,2.22,4=4,48\left(l\right)\)

16 nCO2=0,2mol

PTHH: 2CO+O2=>2CO2

         0,2<--0,1<---0,2

=> mO2=0,2.32=6,4g

=> khối lượng Oxi phản ứng với H2 là :

9,6-6,4=3,2g

=> nH2O=3,2:32=0,1mol

PTHH: 2H+O2=>H2O

b)

           0,2<-0,1<-0,2

=> mH2=2.0,2=0,4g

mCO =0,2.28=5,6g

=> m hh=5,6+0,4=6g

CuO+H2-to--->Cu+H2O 

0,6----0,6
nCuO =48/80=0,6 (mol)
==>VH2 =0,6×22,4=13.44(l)

17.

\(n_{Fe}=\dfrac{5,6}{56}=0,1mol\)

\(m_{H_2SO_4}=200.19,6\%=39,2g\)

\(n_{H_2SO_4}=\dfrac{39,2}{98}=0,4mol\)

\(Fe+H_2SO_4\rightarrow FeSO_4+H_2\)

0,1 <   0,4                                 ( mol )

0,1       0,1              0,1        0,1   ( mol )

\(V_{H_2}=0,1.22,4=2,24l\)

Chất còn dư là H2SO4

\(m_{H_2SO_4\left(dư\right)}=\left(0,4-0,1\right).98=29,4g\)

\(\left\{{}\begin{matrix}m_{FeSO_4}=0,1.152=15,2g\\m_{H_2}=0,1.2=0,2g\end{matrix}\right.\)

\(m_{ddspứ}=5,6+200-0,1.2=205,4g\)

\(\left\{{}\begin{matrix}C\%_{FeSO_4}=\dfrac{15,2}{205,4}.100=7,4\%\\C\%_{H_2}=\dfrac{0,2}{205,4}.100=0,09\%\\C\%_{H_2SO_4\left(dư\right)}=\dfrac{29,4}{205,4}.100=14,31\%\end{matrix}\right.\)

\(n_{Fe}=\dfrac{5,6}{56}=0,1\left(mol\right)\)
\(m_{H_2SO_4}=\dfrac{200.19,6}{100}=39,2\left(g\right)\)
\(n_{H_2SO_4}=\dfrac{39,2}{98}=0,4\left(mol\right)\)
pthh : \(Fe+H_2SO_4->FeSO_4+H_2\)
 LTL: 
\(\dfrac{0,1}{1}< \dfrac{0,4}{1}\)
=> H2SO4 dư 
=> \(n_{H_2}=0,1mol\)
=> \(V_{H_2}=0,1.22,4=2,24\left(L\right)\)
theo pthh :\(n_{H_2SO_4\left(p\text{ư}\right)}=n_{Fe}=0,1\left(mol\right)\)
=> \(n_{H_2SO_4\left(d\right)}=0,4-0,1=0,3\left(mol\right)\)
=> \(m_{H_2SO_4}=98.0,3.29,4\left(g\right)\)
ta có mdd =5,6+39,2 = 44,8 (g)
\(C\%=\dfrac{5,6}{44,8}.100\%=12,55\)

\(2Cu+O_2\rightarrow\left(t^o\right)2CuO\\ n_{CuO}=n_{Cu}=\dfrac{6,4}{64}=0,1\left(mol\right);n_{O_2}=\dfrac{0,1}{2}=0,05\left(mol\right)\\ a,V_{O_2\left(đktc\right)}=0,05.22,4=1,12\left(l\right)\\ V_{kk\left(đktc\right)}=\dfrac{100.1,12}{20}=5,6\left(l\right)\\ b,m_{CuO}=0,1.80=8\left(g\right)\\ c,2R+O_2\rightarrow\left(t^o\right)2RO\\ n_R=2.n_{O_2}=2.0,05=0,1\left(mol\right)\\ M_R=\dfrac{2,4}{0,1}=24\left(\dfrac{g}{mol}\right)\\ \Rightarrow R:Magie\left(Mg=24\right)\)

2KMnO₄--->K₂MnO₄ + MnO₂ + O₂

0,04-------------------------------------0,02 mol

n _KMnO4=6,32\158=0,04 mol

=>V_O2=0,02.22,4=0,448l

2Zn+O₂-to>2ZnO

         0,02---0,04 mol

=>m ZnO=0,04.81=3,24g

PTHH: \(4P+5O_2\underrightarrow{t^o}2P_2O_5\)

a) Ta có: \(n_P=\dfrac{3,1}{31}=0,1\left(mol\right)\) 

\(\Rightarrow n_{P_2O_5}=0,05\left(mol\right)\) \(\Rightarrow m_{P_2O_5}=0,05\cdot142=7,1\left(g\right)\)

b) Ta có: \(n_{O_2}=\dfrac{5,6}{22,4}=0,25\left(mol\right)\)

Xét tỉ lệ: \(\dfrac{0,1}{4}< \dfrac{0,25}{5}\) \(\Rightarrow\) Photpho p/ứ hết, Oxi còn dư

\(\Rightarrow n_{O_2\left(dư\right)}=0,25-0,125=0,125\left(mol\right)\)

\(\Rightarrow m_{O_2\left(dư\right)}=0,125\cdot32=4\left(g\right)\)

\(a) n_P = \dfrac{3,1}{31} = 0,1(mol)\\ 4P + 5O_2 \xrightarrow{t^o} 2P_2O_5\\ n_{P_2O_5} = \dfrac{1}{2}n_P = 0,05(mol)\\ m_{P_2O_5} = 0,05.142 = 7,1(gam)\\ b) n_{O_2} = \dfrac{5,6}{22,4} = 0,25(mol)\\ \dfrac{n_P}{4} = 0,025<\dfrac{n_{O_2}}{5} = 0,05 \to O_2\ dư\\ n_{O_2\ pư} = \dfrac{5}{4}n_P = 0,125(mol) \Rightarrow m_{O_2\ dư} = (0,25 - 0,125).32 = 4(gam)\)

PTHH : \(4P+5O_2\rightarrow2P_2O_5\)

a) Số mol P tham gia phản ứng : \(n_P=\dfrac{m_P}{M_P}=\dfrac{3,1}{31}=0,1\left(mol\right)\)

Theo PTHH : \(n_{P_2O_5}=2n_P=0,2\left(mol\right)\)

Khối lượng P₂O₅ tạo thành : \(m_{P_2O_5}=M_{P_2O_5}\cdot n_{P_2O_5}=142\cdot0,2=28,4\left(g\right)\)

b) Số mol O₂ tham gia phản ứng : \(n_{O_2}=\dfrac{V_{O_2}}{22,4}=\dfrac{5,6}{22,4}=0,25\left(mol\right)\)

Theo bài ra ta có :

\(\dfrac{n_P\left(baicho\right)}{n_P\left(PTHH\right)}=\dfrac{0,1}{4}=0,025\left(mol\right)\); \(\dfrac{n_{O_2}\left(baicho\right)}{n_{O_2}\left(PTHH\right)}=\dfrac{0,25}{5}=0,05\left(mol\right)\)

Vì 0,025 < 0,05 => P hết, O₂ dư

Khối lượng O₂ dư : \(m_{O_2}=M_{O_2}\cdot n_{O_2}=32\left(0,05-0,025\right)=32\cdot0,025=0,8\left(g\right)\)