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A 
B 
Fe3O4
) nung nóng. Sau khi phản ứng xảy ra hoàn toàn thu được m gam chất rắn.
\(C+O_2\xrightarrow[]{t^o}CO_2\)
\(S+O_2\xrightarrow[]{t^o}SO_2\)
\(4P+5O_2\xrightarrow[]{t^o}2P_2O_5\)
\(H_2+\dfrac{1}{2}O_2\xrightarrow[]{t^o}H_2O\)
\(4Na+O_2\rightarrow2Na_2O\)
\(Mg+\dfrac{1}{2}O_2\xrightarrow[]{t^o}MgO\)
\(4Al+3O_2\xrightarrow[]{t^o}2Al_2O_3\)
\(3Fe+2O_2\xrightarrow[]{t^o}Fe_3O_4\)
\(Cu+\dfrac{1}{2}O_2\xrightarrow[]{t^o}CuO\)
\(CH_4+2O_2\xrightarrow[]{t^o}CO_2+2H_2O\)
\(4FeS_2+11O_2\xrightarrow[]{t^o}2Fe_2O_3+8SO_2\)
\(C_2H_6O+3O_2\xrightarrow[]{t^o}2CO_2+3H_2O\)
C+ O2 -to-> CO2
S+ O2 -to-> SO2
2 Cl2 + 7 O2 -to-> 2 Cl2O7
4P +5 O2 -to-> 2 P2O5
4Al + 3 O2 -to-> 2 Al2O3
4 Na+ O2 -to-> 2 Na2O
Mg + 1/2 O2 -to-> MgO
3 Fe +2 O2 -to-> Fe3O4
4 FeS2 + 11 O2 -to,xt-> 8 SO2 + 2 Fe2O3
H2 + 1/2 O2 -to->H2O
2 Ag + 1/2 O2 -to-> Ag2O
C2H6O + 3 O2 -to-> 2 CO2 + 3 H2O
CH4 + 2 O2 -to-> CO2 + 2 H2O
Cu + 1/2 O2 -to-> CuO
\(Na_2CO_3+2HCl\rightarrow2NaCl+CO_2+H_2O\)
\(Na_2CO_3+Ba\left(OH\right)_2\rightarrow2NaOH+BaCO_{3\downarrow}\)
\(CaCO_3+2HCl\rightarrow CaCl_2+H_2O+CO_2\)
\(K_2SO_4+Ba\left(OH\right)_2\rightarrow2KOH+BaSO_{4\downarrow}\)
\(2HCl+Ba\left(OH\right)_2\rightarrow BaCl_2+2H_2O\)
\(2HCl+Mg\left(OH\right)_2\rightarrow MgCl_2+2H_2O\)
\(Fe+2HCl\rightarrow FeCl_2+H_2\)
\(Mg+2HCl\rightarrow MgCl_2+H_2\)
\(Al+3HCl\rightarrow AlCl_3+3H_2\)
Pt : Fe + 2HCl → FeCl2 + H2
Mg + 2HCl → MgCl2 + H2
2Al + 6HCl → 2AlCl3 + 3H2
Chúc bạn học tốt
a)
$PbO + H_2 \xrightarrow{t^o} Pb + H_2O$
$2H_2 + O_2 \xrightarrow{t^o} 2H_2O$
$Fe_3O_4 + 4H_2 \xrightarrow{t^o} 3Fe + 4H_2O$
b)
$2K + 2H_2O \to 2KOH$( Kali hidroxit) $+ H_2$
$CaO + H_2O \to Ca(OH)_2$ (Canxi hidroxit)
$SO_3 + H_2O \to H_2SO_4 $ (Axit sunfuric)
$N_2O_5 + H_2O \to 2HNO_3$ (Axit nitric)
a, \(2H_2+O_2\underrightarrow{t^O}2H_2O\)
\(4K+O_2\underrightarrow{t^o}2K_2O\)
\(Ba+\dfrac{1}{2}O_2\underrightarrow{t^o}BaO\)
\(3Fe+2O_2\underrightarrow{t^o}Fe_3O_4\)
\(Cu+\dfrac{1}{2}O_2\underrightarrow{t^o}CuO\)
\(CH_4+2O_2\underrightarrow{t^o}CO_2+2H_2O\)
b, \(CuO+H_2\underrightarrow{t^o}Cu+H_2O\)
\(PbO+H_2\underrightarrow{t^o}Pb+H_2O\)
\(HgO+H_2\underrightarrow{t^o}Hg+H_2O\)
\(Fe_3O_4+4H_2\underrightarrow{t^o}3Fe+4H_2O\)
c, \(Na+HCl\rightarrow NaCl+\dfrac{1}{2}H_2\)
\(Mg+2HCl\rightarrow MgCl_2+H_2\)
\(2Al+6HCl\rightarrow2AlCl_3+3H_2\)
d, \(2Na+2H_2O\rightarrow2NaOH+H_2\)
\(Ba+2H_2O\rightarrow Ba\left(OH\right)_2+H_2\)
\(CaO+H_2O\rightarrow Ca\left(OH\right)_2\)
\(Na_2O+H_2O\rightarrow2NaOH\)
\(SO_2+H_2O⇌H_2SO_3\)
\(SO_3+H_2O\rightarrow H_2SO_4\)
\(n_{Zn}=\dfrac{8,125}{65}=0,125\left(mol\right)\\ m_{HCl}=\dfrac{100.18,25}{100}=18,25\left(g\right)\\
n_{HCl}=\dfrac{18,25}{36,5}=0,5\\ pthh:Zn+2HCl\rightarrow ZnCl_2+H_2\uparrow\)
0,125 0,125 (mol )
\(\Rightarrow V_{H_2}=0,125.22,4=2,8\left(l\right)\\
\)
\(C\%=\dfrac{8,125}{8,125+18,25}.100\%=30,8\%\)
Bài 18:
Ta có: \(n_{Zn}=\dfrac{8,125}{65}=0,125\left(mol\right)\)
\(m_{HCl}=100.18,25\%=18,25\left(g\right)\Rightarrow n_{HCl}=\dfrac{18,25}{36,5}=0,5\left(mol\right)\)
a, PT: \(Zn+2HCl\rightarrow ZnCl_2+H_2\)
b, Xét tỉ lệ: \(\dfrac{0,125}{1}< \dfrac{0,5}{2}\), ta được HCl dư.
Theo PT: \(n_{H_2}=n_{Zn}=0,125\left(mol\right)\)
\(\Rightarrow V_{H_2}=0,125.22,4=2,8\left(g\right)\)
\(m_{H_2}=0,125.2=0,25\left(g\right)\)
c, Theo PT: \(\left\{{}\begin{matrix}n_{ZnCl_2}=n_{Zn}=0,125\left(mol\right)\\n_{HCl\left(pư\right)}=2n_{Zn}=0,25\left(mol\right)\end{matrix}\right.\)
\(\Rightarrow n_{HCl\left(dư\right)}=0,25\left(mol\right)\)
Có: m dd sau pư = 8,125 + 100 - 0,25 = 107,875 (g)
\(\Rightarrow\left\{{}\begin{matrix}C\%_{ZnCl_2}=\dfrac{0,125.136}{107,875}.100\%\approx15,76\%\\C\%_{HCl\left(dư\right)}=\dfrac{0,25.36,5}{107,875}.100\%\approx8,46\%\end{matrix}\right.\)
Bạn tham khảo nhé!
a) PTHH: Zn + H2SO4 -> ZnSO4 + H2
H2 + CuO -to-> Cu + H2O
b) nH2=nZnSO4= nZn=0,3(mol)
nCuO=36/80=0,45(mol)
Ta có: 0,3/1 <0,45/1
=>H2 hết, CuO dư.
=> Sau phản ứng các chất thu được gồm có: ZnSO4, Cu và CuO(dư)
nCuO(P.ứ)=nCu=nH2=0,3(mol)
=> nCuO(dư)=0,45-0,3=0,15(mol)
mCuO(dư)=0,15.80=12(g)
mCu=0,3.64=19,2(g)
mZnSO4=0,3. 161= 48,3(g)
Tự cân bằng
C + O2 -to-> CO2
Mg + O2 -to-> MgO
H2 + O2 -to-> H2O
Zn + O2 -to-> ZnO
C2H6 + O2 -to-> CO2 + H2O
FeS + O2 -to-> Fe2O3 + SO2
C3H8O + O2 -to-> CO2 + H2O