question_answer 41)

In the following questions only one option is correct. Which of the following is not an example of redox reaction? (a)\[CuO+{{H}_{2}}\to Cu+{{H}_{2}}O\]                                 (b) \[F{{e}_{2}}{{O}_{3}}+3CO\to 2Fe+3C{{O}_{2}}\] (c)\[2K+{{F}_{2}}\to 2KF\]                                                            (d) \[BaC{{l}_{2}}+{{H}_{2}}S{{O}_{4}}\to BaS{{O}_{ & 4}}+2HCl\]

Answer:

(d)\[\overset{+2-1}{\mathop{BaC{{l}_{2}}}}\,+{{H}_{2}}S{{O}_{4}}\to \overset{2+}{\mathop{BaS{{O}_{4}}}}\,+2\overset{-1}{\mathop{HCl}}\,\] It is simply a double decomposition reaction. It does not involve any change in oxidation number, hence it is not a redox reaction.