Câu 10:
\(PCl_3+3H_2O\rightarrow H_3PO_3+3HCl\\ H_3PO_3+3NaOH\rightarrow Na_3PO_3+3H_2O\\HCl+NaOH\rightarrow NaCl+H_2O\\ Đặt:n_{PCl_3}=k\left(mol\right)\\ \Rightarrow n_{H_3PO_3}=k\left(mol\right);n_{HCl}=3k\left(mol\right)\\ Ta.có:n_{NaOH}=3.n_{H_3PO_3}+n_{HCl}=3k+3k\\ \Leftrightarrow0,6=6k\\ \Leftrightarrow k=0,1\left(mol\right)\\ \Rightarrow n_{PCl_3}=0,1\left(mol\right)\\ \Rightarrow Chọn.A\)
Câu 8:
\(n_{NaCl}=\dfrac{8,775}{58,5}=0,15\left(mol\right)\\ NaCl+H_2SO_{4\left(đặc\right)}\rightarrow\left(250^oC\right)NaHSO_4+HCl\uparrow\\ n_{HCl}=n_{NaCl}=0,15\left(mol\right)\\ \Rightarrow C\%_{ddHCl}=\dfrac{0,15.36,5}{0,15.36,5+14,525}.100=27,375\%\\ \Rightarrow Chọn.A\\ MnO_2+4HCl_{đặc}\rightarrow\left(t^o\right)MnCl_2+Cl_2+2H_2O\\ n_{Cl_2\left(thu\right)}=70\%.n_{Cl_2\left(LT\right)}=70\%.\dfrac{0,15}{4}=0,02625\left(mol\right)\\ \Rightarrow V_{Cl_2\left(đktc,thu\right)}=0,02625.22,4=0,588\left(l\right)\\ \Rightarrow Chọn.B\)
