Question

The colour of Cu ions is blue due to which all copper salts are blue but why is the colour of CuO black??

please guys answer it correctly....I request u not to post any irrelevant answers​

Answer 1

Answer:

because its precipitate is black when heated in the presence of caralaye mediate dicromate and tri rather element form blue colour

Answer 2

Answer:

Illustrate variety of substances of which an element can be part:

metal --> blue solution --> blue solid --> black solid --> blue solution (again) --> metal (again).

Conservation of mass and of moles:

We should recover as much copper as we started with.

Same amount of copper present at every stage: same number of moles.

Experience in standard chemical techniques: filtration and quantitative transfers.

Reactions

Cu(s) --> [Cu(H2O)6]2+(aq) --> Cu(OH)2(s) --> CuO(s) --> [Cu(H2O)6]2+(aq) --> Cu(s)