Question

Distinguish between MgO and CuO by using conc HCl

Answer 1

MgO added to HCl and mg displaces h2 to produce Mgcl and H2O..........but
CuO added to HCl Cu cannot displace therefore no reaction...

Answer 2

MgO + 2HCL = MgCL² + H²O CuO + 2HCL = CuCL² + H²O