Bài 3:
\(n_{Fe}=\dfrac{16,8}{56}=0,3\left(mol\right)\\ a,PTHH:3Fe+2O_2\rightarrow\left(t^o\right)Fe_3O_4\\ b,n_{Fe_3O_4}=\dfrac{0,3}{3}=0,1\left(mol\right)\\ \Rightarrow m_{Fe_3O_4}=232.0,1=23,2\left(g\right)\\ c,n_{O_2}=\dfrac{2}{3}.0,3=0,2\left(mol\right)\\ V_{O_2\left(đktc\right)}=0,2.22,4=4,48\left(l\right)\\ V_{kk\left(đktc\right)}=4,48.5=22,4\left(l\right)\)
Câu 4:
\(n_P=\dfrac{m_p}{M_p}=\dfrac{1,24}{31}=0,04mol\)
\(4P+5O_2\rightarrow\left(t^o\right)2P_2O_5\)
4 5 2 ( mol )
0,04 0,05 0,02 ( mol )
\(m_{P_2O_5}=n_{P_2O_5}.M_{P_2O_5}=0,02.142=2,84g\)
\(V_{O_2}=n_{O_2}.22,4=0,05.22,4=1,12l\)
\(V_{kk}=\dfrac{V_{O_2}}{\dfrac{1}{5}}=\dfrac{1,12}{\dfrac{1}{5}}=5,6l\)
