Question

CU ->CUO -> CU(NO3)2 -> CU(OH)2 -> CUO -> CU

Answer 1

2CU+O2=CUO

CUO+2HNO3=CU(NO3)2+H2O

2CU(NO3)2+2H2O=2CU(OH)2+4HNO3

CU(OH)2=CUO+H2O

2CUO=2CU+O2