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In balancing, it is very important to identify the substance whose:

Correct answer: B. Oxidation number is changed

  • A. Physical state is changed
  • B. Oxidation number is changed
  • C. Enthalpy is changed
  • D. All of these

Explanation

In balancing an equation, not only should the moles be balanced on both sides but also the charges. While balancing a chemical equation, we should identify the chemical species whose oxidation number changed during the reaction. It indicates the gain or loss of electrons. As a result, we can identify the number of electrons transferred and thus, balance the equation. Hence, the B option is the correct option.

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About Electrochemistry

Electrochemistry describes electron transfer through oxidation and reduction, identifies oxidizing and reducing agents, and applies oxidation numbers to balance redox equations. It also covers electrode potential and the standard hydrogen electrode, which provides the reference for comparing the reduction tendencies of other electrodes.

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