A sample of copper powder was contaminated with zinc dust. Pure copper
was obtained from it by heating with excess of acid, filtering and washing.
Which of the following acids was used?
(A)Dilute nitric acid
(B)Concentrated nitric acid
(C)Dilute hydrochloric acid
(D) Concentrated sulphuric acid

Question

A sample of copper powder was contaminated with zinc dust. Pure copper
was obtained from it by heating with excess of acid, filtering and washing.
Which of the following acids was used?
(A)Dilute nitric acid
(B)Concentrated nitric acid
(C)Dilute hydrochloric acid
(D) Concentrated sulphuric acid

anonymous · Answer

C.  That's the only one that won't also react with the copper.

anonymous · Answer

yes i concur

anonymous · Answer

hcl wont react with copper ?

anonymous · Answer

diluted it wont cause of coper's pasivisation coat

anonymous · Answer

ok

anonymous · Answer

i remember that we prepaired CuCl2 with concentrated thats why im pretty sure