K+ nước-->....

K+HCl-->....

K+ AgNO3-->....

Ba+ nước -->....

Ba+ HCl-->....

Ba+ KNO3-->....

Fe+ nước -->...

Fe+ HCl-->....

Fe+ ZnSO4-->....

CÂN BẰNG GIÚP MÌNH VỚI Ạ. THANK YOU

PTHH:

$\rm 2K+2H_2O\to 2KOH+H_2 \\ 2K+2HCl\to 2KCl+H_2 \\ 2K+H_2O+2AgNO_3\to Ag_2O+H_2 +2KNO_3\\ Ba+2H_2O\to Ba(OH)_2+H_2 \\ Ba+2HCl\to BaCl_2+H_2 \\ Ba+KNO_3\to ×\\ Fe+H_2O \xrightarrow{t^o}FeO+H_2 \\ Fe+2HCl\to FeCl_2+H_2 \\ Fe+ZnSO_4\to ×$