Question

Ba-BaO-Ba(OH)2-Ba(NO3)2-BaSO4

Answer 1

2Ba+O2=2BaO

BaO+H2O=Ba(OH)2

Ba(OH)2+Mg(NO3)2=Ba(NO3)2+Mg(OH)2

Ba(NO3)2+K2SO4=BaSO4+2KNO3