Câu 22:
$A: Na, Cu, Fe, Al_2O_3$
$B: NaAlO_2$
$D: Al_2O_3, Cu, Fe$
$E: Al(OH)_3$
PTHH:
$CuO+CO\xrightarrow{{t^o}} Cu+CO_2$
$Fe_2O_3+3CO\xrightarrow{{t^o}} 2Fe+3CO_2$
$2Na+2H_2O\to 2NaOH+H_2$
$Al_2O_3+2NaOH\to 2NaAlO_2+H_2O$
$CO_2+NaAlO_2+H_2O\to Al(OH)_3+NaHCO_3$
$Al_2O_3+Ba(OH)_2\to Ba(AlO_2)_2+H_2O$
Câu 20:
Điều chế được $NaCl$, $AlCl_3$, $NaHCO_3$, $Na_2CO_3$, $NaAlO_2$, $NaClO$, $NaClO_3$, $NaClO_4$, $NaH$:
$Na_2O+2HCl\to 2NaCl+H_2O$
$Al_2O_3+6HCl\to 2AlCl_3+3H_2O$
$Na_2O+H_2O\to 2NaOH$
$NaOH+CO_2\to NaHCO_3$
$2NaOH+CO_2\to Na_2CO_3+H_2O$
$2NaOH+Al_2O_3\to 2NaAlO_2+H_2O$
$2HCl\xrightarrow{{\text{đpdd}}} H_2+Cl_2$
$2NaOH+Cl_2\to NaCl+NaClO+H_2O$
$6NaOH+3Cl_2\xrightarrow{{t^o}} 5NaCl+NaClO_3+3H_2O$
$4NaClO_3\xrightarrow{{t^o}} 3NaClO_4+NaCl$
$4NaOH\xrightarrow{{đpnc}} 4Na+2H_2O+O_2$
$2Na+H_2\to 2NaH$
