Bài 4:
1. \(Fe+2HCl\rightarrow FeCl_2+H_2\)
___0,1___0,2_____0,1____0,1 (mol)
2. \(2KMnO_4\underrightarrow{t^o}K_2MnO_4+MnO_2+O_2\)
____0,55_______0,275____0,275___0,275 (mol)
3. \(2KClO_3\underrightarrow{t^o}2KCl+3O_2\)
____11/30____11/30__0,55 (mol)
4. \(Fe+2HCl\rightarrow FeCl_2+H_2\)
___0,1____0,2____0,1____0,1 (mol)
Bài 5:
a, Ta có: \(\left\{{}\begin{matrix}\%m_{Fe}=\dfrac{56}{100}.100\%=56\%\\\%m_{Al}=44\%\end{matrix}\right.\)
b, \(\left\{{}\begin{matrix}\%m_{Mg}=\dfrac{24}{55}.100\%\approx43,64\%\\\%m_{Zn}\approx56,36\%\end{matrix}\right.\)
Bạn tham khảo nhé!
7.a) \(2KMnO_4-^{t^o}\rightarrow K_2MnO_4+MnO_2+O_2\)
b) \(n_{O_2}=\dfrac{1}{2}n_{KMnO_4}=\dfrac{1}{2}.0,25=0,125\left(mol\right)\)
=> \(V_{O_2}=0,125.22,4=2,8\left(g\right)\)
Bài 6:
Ta có: \(n_{Al}=\dfrac{13,5}{27}=0,5\left(mol\right)\)
a, PT: \(2Al+6HCl\rightarrow2AlCl_3+3H_2\)
______0,5___________________0,75 (mol)
b, VH2 = 0,75.22,4 = 16,8 (l)
Bài 7:
Ta có: \(n_{KMnO_4}=\dfrac{39,5}{158}=0,25\left(mol\right)\)
a, PT: \(2KMnO_4\underrightarrow{t^o}K_2MnO_4+MnO_2+O_2\)
________0,25_____________________0,125 (mol)
b, VO2 = 0,125.22,4 = 2,8 (l)
Bài 8:
Ta có: \(\left\{{}\begin{matrix}n_{Fe}=\dfrac{56}{56}=1\left(mol\right)\\n_{Al}=\dfrac{69,5-56}{27}=0,5\left(mol\right)\end{matrix}\right.\)
a, PT: \(Fe+2HCl\rightarrow FeCl_2+H_2\)
______1___________________1 (mol)
\(2Al+6HCl\rightarrow2AlCl_3+3H_2\)
_0,5___________________0,75 (mol)
b, VH2 = (1 + 0,75).22,4 = 39,2 (l)
c, \(\left\{{}\begin{matrix}\%m_{Fe}=\dfrac{56}{69,5}.100\%\approx80,58\%\\\%m_{Al}\approx19,42\%\end{matrix}\right.\)
Bạn tham khảo nhé!
