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Bài 1:
PTHH: \(2C_4H_{10}+13O_2\xrightarrow[]{t^o}8CO_2+10H_2O\)
Ta có: \(n_{C_4H_{10}}=\dfrac{11,6}{58}=0,2\left(mol\right)\)
\(\Rightarrow\left\{{}\begin{matrix}n_{CO_2}=0,8\left(mol\right)\\n_{H_2O}=1\left(mol\right)\end{matrix}\right.\) \(\Rightarrow\left\{{}\begin{matrix}m_{CO_2}=0,8\cdot44=35,2\left(g\right)\\m_{H_2O}=1\cdot18=18\left(g\right)\end{matrix}\right.\)
Bài 2:
PTHH: \(CaCO_3\xrightarrow[]{t^o}CaO+CO_2\uparrow\)
Ta có: \(n_{CO_2}=\dfrac{11,2}{22,4}=0,5\left(mol\right)=n_{CaO}=n_{CaCO_3\left(p.ứ\right)}\)
\(\Rightarrow\left\{{}\begin{matrix}m_{CaO}=0,5\cdot56=28\left(g\right)\\\%m_{CaCO_3\left(p.ứ\right)}=\dfrac{0,5\cdot100}{100}\cdot100\%=50\%\end{matrix}\right.\)
\(n_{CaO}=\dfrac{m}{M}=0,2\left(mol\right)\)
\(PTHH:CaCO_3\rightarrow CaO+CO_2\)
.................0,2............0,2......0,2..........
a, \(m_{CaCO_3}=M.n=20\left(g\right)\)
b, \(V_{CO_2}=n.22,4=4,48\left(l\right)\)
Vậy ...
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 )
\(m_{H_2O}=0,4.18=7,2g\)
PTHH: \(Cu_2S+2O_2\xrightarrow[]{t^o}2CuO+SO_2\)
a) Ta có: \(n_{Cu_2S}=\dfrac{100}{160}=0,625\left(mol\right)\) \(\Rightarrow n_{O_2\left(lýthuyết\right)}=1,25\left(mol\right)\)
\(\Rightarrow V_{O_2\left(thực\right)}=\dfrac{1,25\cdot22,4}{96\%}\approx29,17\left(l\right)\)
b) Sửa đề: "Tính khối lượng KMnO4 để hấp thụ hết SO2"
PTHH: \(5SO_2+2KMnO_4+2H_2O\rightarrow K_2SO_4+2MnSO_4+2H_2SO_4\)
Ta có: \(n_{SO_2\left(thực\right)}=n_{Cu_2S}\cdot96\%=0,6\left(mol\right)\)
\(\Rightarrow n_{KMnO_4}=0,24\left(mol\right)\) \(\Rightarrow m_{KMnO_4}=0,24\cdot158=37,92\left(g\right)\)
c) PTHH: \(SO_2+\dfrac{1}{2}O_2\xrightarrow[V_2O_5]{t^o}SO_3\)
Theo PTHH: \(n_{O_2}=\dfrac{1}{2}n_{SO_2}=0,3\left(mol\right)\) \(\Rightarrow V_{kk}=\dfrac{0,3\cdot22,4}{21\%}=32\left(l\right)\)
d) Bảo toàn nguyên tố Lưu huỳnh: \(n_{H_2SO_4\left(lýthuyết\right)}=n_{SO_2\left(thực\right)}=0,3\left(mol\right)\)
\(\Rightarrow n_{H_2SO_4\left(thực\right)}=0,3\cdot85\%=0,255\left(mol\right)\) \(\Rightarrow m_{ddH_2SO_4}=\dfrac{0,255\cdot98}{10\%}=249,9\left(g\right)\)
\(m_{CO_2}=\dfrac{3,36}{22,4}.44=6,6(g)\)
Áp dụng định luật BTKL: \(m_{\text{hh muối}}=m_{\text{hh oxit}}+m_{CO_2}=76+6,6=82,6(g)\)
\(V_{CO_2}=0,5.22,4=11,2\left(l\right)\)
\(A_{CO_2}=0,5.6.10^{23}=3.10^{23}\) (phân tử \(CO_2\) )
2.
\(n_{CO_2}=\dfrac{2,24}{22,4}=0,1\left(mol\right)\)
=> \(n_C=n_{CO_2}=0,1\left(mol\right)\) (1)
=> \(n_O=2nCO_2=0,1.2=0,2\left(mol\right)\) (*)
\(n_{H_2O}=\dfrac{3,6}{18}=0,2\left(mol\right)\)
=> \(n_H=2n_{H_2O}=0,2.2=0,4\left(mol\right)\) (2)
=> \(n_O=n_{H_2O}=0,2\left(mol\right)\) (**)
\(n_{O_2}=\dfrac{4,8}{22,4}=0,2\left(mol\right)\)
=> \(n_O=2n_{O_2}=2.0,2=0,4\left(mol\right)\) (3)
\(X+O_2\underrightarrow{t^o}CO_2+H_2O\)
Từ (1),(2),(3), (*), (**) suy ra: \(n_C:n_H:n_O=0,1:0,4:0\)
=> Công thức tổng quát của X là \(C_xH_y\)
có: \(x:y=n_C:n_H=0,1:0,4=1:4\)
=> X là: \(CH_4\)
Sơ đồ pứ: \(CH_4+2O_2\underrightarrow{t^o}CO_2+2H_2O\)
\(m_{CH_4}=3,6+0,2.44-0,2.32=6\left(g\right)\)
Gọi x, y là số mol của C và S, ta có:
\(C+O_2\rightarrow CO_2\)
x x x
\(S+O_2\rightarrow SO_2\)
y y y
\(\Rightarrow\left\{{}\begin{matrix}x+y=\dfrac{4,48}{22,4}=0,2\\12x+32y=4,4\end{matrix}\right.\)
\(\Rightarrow\left\{{}\begin{matrix}x=0,1\\y=0,1\end{matrix}\right.mol\)
\(\Rightarrow m_{hh}=0,1.44+0,1.64=10,8g\)
\(a,PTHH:Fe+2HCl\rightarrow FeCl_2+H_2\\ \Rightarrow n_{Fe}=n_{FeCl_2}=\dfrac{11,2}{56}=0,2\left(mol\right)\\ \Rightarrow m_{FeCl_2}=0,2\cdot127=25,4\left(g\right)\\ b,n_{H_2}=n_{Fe}=0,2\left(mol\right)\\ \Rightarrow\left\{{}\begin{matrix}m_{H_2}=0,2\cdot2=0,4\left(g\right)\\V_{H_2\left(đktc\right)}=0,2\cdot22,4=4,48\left(l\right)\end{matrix}\right.\)
\(c,PTHH:2H_2+O_2\rightarrow^{t^0}2H_2O\\ \Rightarrow n_{O_2}=\dfrac{1}{2}n_{H_2}=0,1\left(mol\right)\\ \Rightarrow V_{O_2\left(đktc\right)}=0,1\cdot22,4=2,24\left(l\right)\)
a) CH4 + 2O2 --to--> CO2 + 2H2O
b) \(V_{O_2}=\dfrac{56}{5}=11,2\left(l\right)\)
=> \(n_{O_2}=\dfrac{11,2}{22,4}=0,5\left(mol\right)\)
PTHH: CH4 + 2O2 --to--> CO2 + 2H2O
_____0,25<--0,5-------->0,25
=> VCH4 = 0,25.22,4 = 5,6 (l)
c)
mCO2 = 0,25.44 = 11 (g)
Bài 1:
\(n_{C_4H_{10}}=\frac{m}{M}=\frac{11,6}{58}=0,2mol\)
PTHH: \(2C_4H_{10}+13O_2\rightarrow^{t^o}8CO_2\uparrow+10H_2O\)
0,2 1,3 0,8 1 mol
\(\rightarrow n_{O_2}=n_{C_4H_{10}}=\frac{13.0,2}{2}=1,3mol\)
\(V_{O_2\left(ĐKTC\right)}=n.22,4=1,3.22,4=29,12l\)
\(\rightarrow n_{CO_2}=n_{C_4H_{10}}=\frac{8.0,2}{2}=0,8mol\)
\(m_{CO_2}=n.M=0,8.44=35,2g\)
\(\rightarrow n_{H_2O}=n_{C_4H_{10}}=\frac{10.0,2}{2}=1mol\)
\(m_{H_2O}=n.M=1.18=18g\)