Choose all of the statements from below which are true about oxidation and reduc
ID: 972177 • Letter: C
Question
Choose all of the statements from below which are true about oxidation and reduction. Oxidation and reduction are opposite processes with respect to bookkeeping electrons. Oxidation is what happens when an element in a substance increases its oxidation number. Electrons appear on the right side of an oxidation half reaction. An oxidant is an oxidizing agent, which becomes reduced during the course of a redox reaction. Reduction is what happens when an element in a substance decreases its oxidation number. Electrons appear on the left side of a reduction half reaction. A reductant is an reducing agent, which becomes oxidized during the course of a redox reaction.
Explanation / Answer
General example that will be used for each question:
2Mg(s) + O2 (g)--> 2MgO(s)
1. Oxidation and reduction are opposite processes with respect to bookkeeping electrons. Yes, in an oxidation process an element loses electrons, and it oxidation number increases while in the reduction process the electrons given by the oxidation process will be accepted and therefore the oxidation number of the reduced element decreases. In the example, you can see that the Mg releases 4 electrons that will be accepted by the oxygen, therefore, the oxidation number of the Mg increases (more positive) meanwhile the oxidation number of the O2 decreases (more negative).
2Mg --> 2 Mg2+ + 4e-
O2 +4e- --> 2O2-
2. Oxidation is what happens when an element in a substance increases its oxidation number. Yes, if an element releases electrons, meaning it is oxidized, the oxidation number will increase, leaving the Mg more positive. The example of this:
2Mg --> 2 Mg2+ + 4e-
3. Electrons appear on the right side of an oxidation half reaction. As I described it before, you can see the electrons on the right side of the oxidation half reaction
2Mg --> 2 Mg2+ + 4e-
4. An oxidant is an oxidizing agent, which becomes reduced during the course of a redox reaction. Yes by definition the oxidizing agent is reduced in the reaction, for our example, the oxidizing agent will be the O2.
O2 +4e- --> 2O2- The oxidation number of the oxygen goes from "0" to "2-". So, the oxygen is reduced
5. Reduction is what happens when an element in a substance decreases its oxidation number. Yes, I mentioned before. It decreases that means the oxidation number becomes less positive or more negative.
O2 +4e- --> 2O2-
6. Electrons appear on the left side of a reduction half reaction. Yes, here is the example of this.
O2 +4e- --> 2O2-
7.A reductant is a reducing agent, which becomes oxidized during the course of a redox reaction. Yes, for our example the Mg is the reducing agent because it releases the electrons.
2Mg --> 2 Mg2+ + 4e-