1.$Mg_{}$ $+ _{}$ $2HCl_{}$ $\rightarrow$ $MgCl_{2}$ + $H_{2}$ ↑
2.$Fe_{}$+ $CuSO_{4}$ $\rightarrow$ $FeSO_{4}$ + $Cu_{}$ ↓
3.$H_{2}$ + $O_{2}$ $\xrightarrow[]{t^{o}}$ $H_{2}$$O_{}$
4.$Na_{2}$$SO_{4}$ + $BaCl_{2}$ $\rightarrow$ $2NaCl_{}$ + $BaSO_{4}$↓
5. Phải tạo ra kali nitrat chứ bạn
$2KOH_{}$ + $Fe(NO_{3})$$_{2}$ $\rightarrow$ $2K_{}$$NO_{3}$ + $Fe(OH)_{2}$↓
6. $Fe_{2}$$O_{3}$ + $3H_{2}$ $\xrightarrow[]{t^{o}}$ $2Fe_{}$ + $3H_{2}$$O_{}$
