Question

Chapter 21 Saved 8 attempts left Check my work Be sure to answer all parts. 7.14 points Balance the following skeleton reaction and identify the oxidizing and reducing agents. You do not need to include the states with the identities of the oxidizing and reducing agents. Aso - (aq) + NO2 (aq) → As02 (aq) + NO3(aq) [basic] eBook A50;c) + NO +H,09 450," + NO3 con + 2OH(aq) (ag) Print The oxidizing agent is As0,- References The reducing agent is Report problem No, ® Hint Solution Guided Solution

Second time posting this. Can someone point out why the answers are marked as incorrect? This question is on the site numerous times and The balanced equation has some variance, but all of the responses have the reducing agent as NO2-, and the last time I posted this the person that replied gave the exact same answers that you can see in the screen shot.

Answer 1

Ans :-

Follow the steps :

Step.1 :- Balance the atoms other than hydrogen and oxygen firstly.

Step.2 :- Balance the oxygen atom by adding number of H2O.

Step.3 :- Balance the hydrogen atom by adding number of H+.

Step.4 :- Balance the charge on both side by adding number of electrons.

Step.5 :- Balance the equation in acidic medium and then converted it into basic medium by adding same number of moles of OH- on both the sides as the number of H+.

Oxidation half cell reaction is :

NO2- + H2O --------------> NO3- + 2H+ + 2e- ...............(1)

Reduction half cell reaction is :

AsO43- + 4H+ + 2e---------------> AsO2- + 2H2O ..............(2)

add both the equations :

AsO43- + NO2- + 2H+ --------------> AsO2- + NO3- + H2O (acidic medium)

Adding 2 OH- on both the sides

AsO43- + NO2- + H2O --------------> AsO2- + NO3- + 2OH-   (basic medium)

Therefore,

Balance chemical equation is :

AsO43- + NO2- + H2O --------------> AsO2- + NO3- + 2OH-

Because, NO2- undergoes oxidation, therefore NO2- is the Reducing agent.

and

Because, AsO43- undergoes reduction therefore AsO43- is the Oxidizing agent.