\(n_{HCl}=n_{H2SO4}=0,5.0,2=0,1(mol)\\ m_{HCl}=0,1.36,5=3,65(g)\\ m_{H2SO4}=0,1.98=9,8(g)\\ BTKL:\\ m_{muối}=12+3,65+9,8=25,45g\\ \to A\)

\(a/ \\ 2KClO_3 \buildrel{{t^o}}\over\longrightarrow 2KCl+O_2\\ 4P+5O_2 \to 2P_2O_5\\ P_2O_5+3H_2O \to 2H_3PO_4 b/ \\ CaCO_3\buildrel{{t^o}}\over\longrightarrow CaO+CO_2\\ CaO+H_2O \to ca(OH)_2\)

Làm thử đi âm mà

\(a/\\ M+2nHCl \to MCl_n+nH_2\\ n_{H_2}=\frac{5,6}{22,4}=0,25(mol)\\ n_M=\frac{1}{n}.n_{H_2}=\frac{1}{n}.0,25=\frac{0,25}{n}(mol)\\ M_M=\frac{16,25.n}{0,25}=65.n(g/mol)\\ \text{Chạy biện luân:}\\ \Rightarrow n=1; R=65(Zn)\\ b/\\ Zn+2HCl\to ZnCl_2+H_2\\ n_{HCl}=2.n_{H_2}=2.0,25=0,5(mol)\\ V_{HCl}=\frac{0,5}{0,2}=2,5M \)

\(Ba+2HCl \to BaCl_2+H_2\\ n_{Ba}=\frac{13,7}{137}=0,1(mol)\\ n_{H_2}=n_{Ba}=0,1(mol)\\ V_{H_2}=0,1.22,4=2,24(l)\\ \text{Vậy chon đáp án C }\)

Bài giải hệ ra âm

\(CuO+2HCl \to CuCl_2+H_2O\\ Al_2O_3+6HCl \to 2AlCl_3+3H_2O\\ n_{CuO}=a(mol)\\ n_{Al_2O_3}=b(mol)\\ n_{HCl}=2a+6b=0,08(1)\\ m_{muối}=135a+267b=4,02(2)\\ (1)(2)\\ a=b=0,01(mol)\\ m_{dd}=4,02+0,01.(80+102)=5,84g\\ C\%_{CuO}=\frac{0,01.80}{5,84}.100\%=13,7\%\\ C\%_{Al_2O_3}=\frac{0,01.102}{5,84}.100\%=17,4\%\)

\(n_{NO}=\frac{1,12}{22,4}=0,05(mol)\\ \text{Bảo toàn e::}\\ 3n_{NO}=10n_{N_2}\\ \to N_2=\frac{0,05.3}{10}=0,015(mol)\\ V_{N_2}=0,015.22,4=0,336(l)\)

\(n_{CO_2}=\frac{264}{44}=6(mol)\\ C+O_2\buildrel{{t^o}}\over\longrightarrow CO_2\\ n_{C}=n_{CO_2}=6(mol)\\ m_{C}=6.12=72(g)\\ \%m_{\text{tạp chât}}=\frac{120-72}{120}.100\%=40\%\)