I conducted some experiment and I want to know the resulting redish black thing I placed two electrodes in a jar
and poured the sparking water with lemon flavor.
After about 5 hours, the water turned to blue and
the negative probe had the redish black thing.
I'd like to know what it is. Please, reply for me.


Materials : 9V battery, battery holder&amp;wire, jar, copper wire and trevi (sparkling 
water)

Connecting battery

After about 5 hours

Result : redish and black thing.
Solvated copper(II) ions for the blue color, copper(II) oxide for the black (as hinted by IvanNeretin). To prove this hypothesis, one could dissolve the copper oxide in sulphuric acid, neutralize the solution and add ammonia. The deep blue color indicates the $\ce{[Cu(NH3)4(H2O)2]^{2+}}$ complex. The latter can also be done for the blue solution currently present.