Which of the following best identifies the redox reaction:
Correct answer: B. Transfer of electron
- A. Transfer of proton
- B. Transfer of electron
- C. Absorption of light
- D. Exchange of ions
Explanation
Oxidation is loss of electrons and reduction is gain, so a redox reaction is defined by electron transfer and by the change in oxidation number that accompanies it. Proton transfer defines an acid base reaction in the Bronsted sense, which is the closest distractor. Simple exchange of ions, as in a precipitation, involves no change in oxidation number at all.
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About Oxidation and Reduction
Oxidation involves loss of electrons, increase in oxidation number or addition of oxygen, while reduction involves electron gain, decrease in oxidation number or removal of oxygen. The topic covers oxidising and reducing agents, oxidation-number changes, redox equations and the distinction between oxidation at the anode and reduction at the cathode.
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