Which of the following reaction is an example of autoreduction?

Options

A. `Fe(3)O_(4)+4CO to 3Fe+4CO_(2)`
B. `Cu_(2)O+C to 2Cu+CO`
C. `Cu^(2+)(aq)+Fe(s) to Cu(s) +Fe^(2+)(aq)`
D. `Cu_(2)O+(1)/(2)Cu_(2)S to 3Cu+(1)/(2)SO_(2)`

Answer

D

Explanation

(d) `Cu_(2)O+(1)/(2)Cu_(2)S to 3Cu+(1)/(2)SO_(2)`
This reaction includes reduction of copper (I) oxide by copper (I) sulphide. In this process, copper is reduced by itself hence this process is known as autoreduction and the solidified copper. So, obtained is known as blister copper.