(i) A depressant prevents a certain type of particle to come to the froth.

(ii) Copper matte contains Cu2S and ZnS.

(iii) The solidified copper obtained from the reverberatory furnace has blistered appearance due to evolution of SO2 during the extraction.

(iv) Zinc can be extracted by self-reduction.

Correct Answers:

(i) A depressant prevents a certain type of particle to come to the froth.

(iii) The solidified copper obtained from the reverberatory furnace has blistered appearance due to evolution of SO2 during the extraction.

Explanation: Copper matte does not contains Cu2S and ZnS and zinc cannot be extracted by self-reduction method.