2012 HSC multiple choice - HELP NEEDED (1 Viewer)

[ragingcurry]

In question 13 you have to refer to a redox reaction

It asks you to identify the oxidising agent in the reaction

I answered A (Hydrogen ion) but the answer is D

Why is it D?

Isn't Cr2O72- being oxidized so shouldn't it be the hydrogen ion which is the oxidizing agent?

Any help would be appreciated

 

[ml125]

In this reaction Cr2O7(2-) is being reduced, and the Fe(2+) is being oxidised. Therefore Cr2O7(2-) is the oxidising agent.

In questions like these it is best to check your data sheet, this makes it easier to identify what is being reduced/oxidised.

 

[Shuuya]

Fe²⁺ becomes Fe³⁺, so it's actually the species being oxidised.

Oops, ml125 beat me

 

[ragingcurry]

Thanks Shuuya and ml125

 

[piethepker]

How would you do 14?

 

[Shuuya]

How would you do 14?

1.36 + -0.77 = 0.59



Therefore, (A)