Chemistry Electrochemistry UHS 2024
PMDC Verified Question 2 of 73
Which step is irrelevant with respect to balancing of redox equations by oxidation number method?
A
Split the reaction into two half reactions
B
Assign oxidation number to all the atoms involved in the equation
C
Identify the element undergoing a change in oxidation number
D
Equalize the number of electrons lost and gained
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option A: Split the reaction into two half reactions
Concept:

There are two distinct methodologies for balancing redox equations: the Oxidation Number Method and the Ion-Electron (Half-Reaction) Method.

Solution:

  • In the Oxidation Number Method, the entire skeleton equation is kept intact. You identify the changes in oxidation states and cross-multiply coefficients directly within the single equation to balance the total electron transfer.


  • Splitting the equation into two physically separate equations (an oxidation half and a reduction half) is the defining, exclusive first step of the Ion-Electron Method.


  • Therefore, splitting is entirely irrelevant to the oxidation number method.


Why other options are incorrect:

Options B, C, and D are mandatory, foundational steps for executing the oxidation number method.

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