Question

Ba→BaO→BaCl2→Ba(NO3)2→Ba(OH)2

Answer 1

2Ba+O2->2Ba0
BaO+2HCl->BaCl2+H20
BaCl2+2HNO3->Ba (NO3)2+2HCl
Ba (NO3)2+2H2O->Ba (OH)2+2HNO3