Hi...

Let me tell you the answer first....

1 )   aqueous sodium hydroxide + X   ----->  green PRECIPITATE

                    X =  iron ( ii ) compound

  EXPLANATION :

                    Let us take FeSO4 as iron ( ii ) compound

                    If i react FeSO4 and NaSO4, it will be a double decomposition reaction...

                    The two compounds dissociate to form,

      FeSO4 (aq)   ----------->    FE2+ + SO4 2-

      2NaOH (aq)  ---------->     2Na+ + 2OH-

                 Then, Fe 2+ will react with 2OH- and 2Na+ will react with SO4 2- to give Fe(OH)2 and Na2SO4

                     Hence the reaction goes like,

      FeSO4 (aq) + 2 NaOH (aq)  ---------->  Fe(OH)2 ( green precipitate ) + Na2SO4

--------------------------------------------------------------------------------------------------------------

2 )   Aqueous sodium hydroxide + Y --------->  light blue precipitate

                Y = copper ( ii ) compound

Explanation :

                 Let me take copper sulphate as copper ( ii ) compound

                 If i react NaOH and CUSO4, its a double decomposition reaction.

  CuSO4( aq)+ 2NaOH(aq)   ----------->  Cu(OH)2 ( light blue precipitate )+ Na2SO4

( the procedure is as same as the previous reaction )

hence,

X = iron ( ii )

Y = copper ( ii )

          THANK U !!!! HOPE IT HELPS YOU.....