2 K3PO4 + 3 BaCl2 = 6 KCl + Ba3(PO4)2
reaction type: double replacement
2 Al(OH)3 + 3 H2SO4 = Al2(SO4)3 + 6 H2O
reaction type: double replacement
2 HCl + K2CO3 = 2 KCl + H2O + CO2
i think there are two reactions here, so double replacement and decomposition
2 AgNO3 + Na2CO3 = Ag2CO3 + 2 NaNO3
reaction type: double replacement
2 Al2O3 = 4 Al + 3 O2
reaction type: decomposition