Why do you use hydrochloric acid to wash copper? Why is it also important to do a final wash with water?

I recently did a chemistry experiement in which solid copper reacted with copper (II) chloride to form iron (II) chloride and solid copper. We used 0.5 M of hydrochloric acid to wash the copper and then we used distilled water as the final wash.





My question is: why did we use hydrochloric acid to wash the copper, and then use water as the final wash? Also, i need to use a balanced equation to prove my answer. I'd appreciate any help i could get. :)Why do you use hydrochloric acid to wash copper? Why is it also important to do a final wash with water?
With dilute Hydrochloric Acid copper dissolves to form copper chloride.Thus copper looks clean.If it is not washed with water,the copper chloride,with contact of oxygen from air will turn to cupric oxide which again makes copper to look unclean.


If you will use concentrated Hydrochloric acid,the copper will become passive (will not dissolve) and will not look clean.


Your expt seems absurd.to form iron chloride unless there is any impurity of containing iron in one of the components.





CU+2HCL=CUCL + H


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