Oxidation – Reduction Reactions

For #s 1 – 6, consider each of the following atom/ion pairs and indicate how many electrons have been gained or lost, balance the reaction if necessary, and tell if that represents oxidation or reduction:

 

1)              Mn⁺⁷   ?    Mn⁺² 

 

 

2)              Cl₂   ?    Cl^-

 

 

3)              Fe⁺²   ?    Fe⁺³ 

 

 

4)              S^-2   ?    S 

 

 

5)              Cu⁺   ?    Cu⁺²   

 

 

6)              Br^-   ?    Br₂  

 

 

For #s 7 – 10: (1) assign oxidation numbers to each atom in the following reactions; (2) write the oxidation and reduction half reactions; (3) identify the oxidizing agent & reducing agent.

 

 

7)    Zn_(s)  +  Cu²⁺_(aq)  ?  Zn⁺²_(aq)  +  Cu_(s) 

 

oxidation half reaction:

 

reduction half reaction:

 

oxidizing agent:

reducing agent:

 

 

 

8)    Cl_2(g)  +  2Br^-_(aq)  ?  2Cl^-_(aq)  +  Br_2(s) 

 

oxidation half reaction:

 

reduction half reaction:

 

oxidizing agent:

reducing agent:

 

 

 

9)    Mg_(s)  +  Ca²⁺_(aq)  ?  Mg⁺²_(aq)  +  Ca_(s) 

 

oxidation half reaction:

 

reduction half reaction:

 

oxidizing agent:

reducing agent:

 

 

 

10) Fe_(s)  +  Ni³⁺_(aq)  ?  Fe⁺²_(aq)  +  Fe_(s) 

 

oxidation half reaction:

 

reduction half reaction:

 

oxidizing agent:

reducing agent:

 

 

 

11) SO_2(g)  +  H₂O_(l)  ?  H₂SO_4(aq)  

 

oxidation half reaction:

 

reduction half reaction:

 

oxidizing agent:

reducing agent:

 

 

 

12) NO_(g)  +  H₂O_(l)  ?  HNO_3(aq) 

 

oxidation half reaction:

 

reduction half reaction:

 

oxidizing agent:

reducing agent: